Analogs of dictyostatin, intermediates therefor and methods of systhesis thereof

ABSTRACT

Dictyostatin and its analogs show great promise as new anticancer agents. The present invention provides dictyostatin analogs, synthetic intermediates for the synthesis of dictyostatin analogs, and synthetic methods for the synthesis of such analogs and intermediates. Dictyostatin analogs can have the following structure or its enantiomer 
     
       
         
         
             
             
         
       
     
     wherein R 1  is H, an alkyl group, an aryl group, an alkenyl group, an alkynyl group, or a halogen atom; R 2  is H, a protecting group, an alkyl group, a benzyl group, a trityl group, —SiR a R b R c , CH 2 OR d , or COR e ; R a , R b  and R c  are independently an alkyl group or an aryl group; R d  is an alkyl group, an aryl group, an alkoxylalkyl group, —R i SiR a R b R c  or a benzyl group, wherein R i  is an alkylene group; R e  is an alkyl group, an allyl group, a benzyl group, an aryl group, an alkoxy group, or —NR g R h , wherein R g  and R h  are independently H, an alkyl group or an aryl group; R 3  is (CH 2 ) n  where n is and integer in the range of 0 to 5, —CH 2 CH(CH 3 ), —CH═CH—, —CH═C(CH 3 ), or —C≡C—; R 4  is 
     
       
         
         
             
             
         
       
     
     wherein R 23a  is H, a protecting group, an alkyl group, a benzyl group, a trityl group, —SiR a R b R c , CH 2 OR d , or COR e , R 23b  is H, a protecting group, an alkyl group, a benzyl group, a trityl group, —SiR a R b R c , CH 2 OR d , or COR e , or R 23a  and R 23b  together form a portion of six-membered acetal ring incorporating CR t R u ; R t  and R u  are independently H, an alkyl group, an aryl group or an alkoxyaryl group; and R 5  is H or OR 2b , wherein R 2b  is H, a protecting group, an alkyl group, an aryl group, a benzyl group, a trityl group, —SiR a R b R c , CH 2 OR d , or COR e ; provided that the compound is not dictyostatin 1.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional of U.S. patent application Ser. No.11/139,949 filed May 27, 2005, which claims benefit of U.S. ProvisionalPatent Application No. 60/574,858 filed May 27, 2004, and is acontinuation in part of U.S. patent application Ser. No. 10/655,916,which claims the benefit of U.S. Provisional Patent Application Ser. No.60/408,503, filed Sep. 6, 2002 and U.S. Provisional Patent ApplicationSer. No. 60/437,736 filed Jan. 2, 2003, the disclosures of which areincorporated herein by reference.

GOVERNMENT INTEREST

This invention was made with government support under grant CA 78039awarded by the National Institutes of Health. The government has certainrights in this invention.

BACKGROUND OF THE INVENTION

The present invention relates to analogs of dictyostatin, intermediatesfor the synthesis of such analogs and methods of synthesis of suchintermediates and analogs.

References set forth herein may facilitate understanding of the presentinvention or the background of the present invention. Inclusion of areference herein, however, is not intended to and does not constitute anadmission that the reference is available as prior art with respect tothe present invention.

The discovery and development of new chemotherapeutic agents for thetreatment of cancer is currently of high importance. Some of the bestcurrently available chemotherapeutic agents are natural products ornatural product analogs. For example, Taxol (paclitaxel) is a naturalproduct that is currently being used to treat patients with breast andovarian cancer among others. A number of analogs of Taxol, includingTaxotere (docetaxel), are also powerful anticancer agents.

Recently, the natural product (+)-discodermolide and its analogs haveshown great promise as anticancer agents. Discodermolide has been shownto have a mechanism of action similar to Taxol, but it is active againstTaxol-resistant cell lines and it is more water soluble than Taxol.Accordingly, it may have a different and/or broader spectrum of actionthan Taxol and be easier to formulate and administer. Analogs ofdiscodernolide have been made and tested for activity. For example, seeMyles, D.C. Emerging microtubule stabilizing agents for cancerchemotherapy, Annual Reports In Medicinal Chem; Academic Press: SanDiego, Calif., 2002; pp 125-132. An interesting feature ofdiscodermolide is that both enantiomers are biologically active.

Recently, an unusual macrolactone natural product dictyostatin 1(sometimes called simply “dictyostatin”) was isolated from two differentsponges and a partial structure was assigned as shown below. See Pettit,G. R.; Cichacz, Z. A. Isolation and structure of dictyostatin 1. In U.S.Pat. No. 5,430,053; 1995; Pettit, G. R.; Cichacz, Z. A.; Gao, F.; Boyd,M. R.; Schmidt, J. M. Isolation and structure of the cancer cell growthinhibitor dictyostatin 1. J. Chem. Soc., Chem. Commun. 1994, 1111-1112.The configurations at C16 and C19 were not yet assigned in the naturalproduct and the absolute configuration was not known. Dictyostatin showsextremely high potencies against and array of cancer cell lines.

Dictyostatin was also shown to stabilize microtubules, likediscodermolide and Taxol. See Wright, A. E.; Cummins, J. L.; Pomponi, S.A.; Longley, R. E.; Isbrucker, R. A. Dictyostatin compounds forstabilization of microtubules. In PCT Int. Appl.; WO62239, 2001.Accordingly, dictyostatin and its analogs show great promise as newanticancer agents. In U.S. patent application Ser. No. 10/655,916, itwas shown that novel analogs of dictyostatin are promising anti-canceragents with potential advantages over Taxol and discodermolide, andtaught the syntheses of these analogs.

It remains desirable to further develop analogs of dictyostatin as wellat to develop methods of synthesis of dictyostatin analogs andintermediates for use in such methods.

SUMMARY OF THE INVENTION

The inventors of the present invention have shown that the proposedstructures of (−)-dictyostatin set forth above are incorrect and thatthe correct structure is as shown below.

In several aspects of the present invention, new and improved methodsand new intermediates for the synthesis of dictyostatin and analogs areprovided. In several other aspects of the present invention, analogs ofdictyostatin as well as methods and intermediates for the synthesis ofthese analogs are provided.

The present inventors have shown that of the dictyostatin analogs setforth in the specification and claims of U.S. patent application Ser.No. 10/655,916, those analogs having a stereostructure similar to thatof dictyostatin are relatively highly biologically active. In thatregard, compounds having the following structure were found to berelatively highly active:

wherein R¹ is H, an alkyl group, an aryl group, an alkenyl group, analkynyl group, or a halogen atom;R² is H, a protecting group, an alkyl group, a benzyl group, a tritylgroup, —SiR^(a)R^(b)R^(c), CH₂OR^(d), or COR^(c);R^(a), R^(b) and R^(c) are independently an alkyl group or an arylgroup;R^(d) is an alkyl group, an aryl group, an alkoxylalkyl group,—R^(i)SiR^(a)R^(b)R^(c) or a benzyl group, wherein R^(i) is an alkylenegroup;R^(e) is an alkyl group, an allyl group, a benzyl group, an aryl group,an alkoxy group, or —NRGR^(h) wherein R^(g) and R^(h) are independentlyH, an alkyl group or an aryl group;R³ is (CH₂), where n is and integer in the range of 0 to 5,—CH₂CH(CH₃)—, —CH═CH—, —CH═C(CH₃)—, or —C≡C—;

R⁴ is

wherein R^(23a) is H, a protecting group, an alkyl group, a benzylgroup, a trityl group, —SiR^(a)R^(b)R^(c), CH₂OR^(d), or COR^(e),R^(23b) is H, a protecting group, an alkyl group, a benzyl group, atrityl group, —SiR^(a)R^(b)R^(c), CH₂OR^(d), or COR^(e), or R^(23a) andR^(23b) together form a portion of six-membered acetal ringincorporating CR^(t)R^(u);R^(t) and R^(u) are independently H, an alkyl group, an aryl group or analkoxyaryl group; andR⁵ is H or OR^(2b), wherein R^(2b) is H, a protecting group, an alkylgroup, an aryl group, a benzyl group, a trityl group,—SiR^(a)R^(b)R^(c), CH₂OR^(d), or COR^(e); provided that the compound isnot dictyostatin 1.

When groups including, but not limited to, —SiR^(a)R^(b)R^(c),CH₂OR^(d), and/or COR^(e) are set forth as a substituent for more thanone group in compounds of the claims and the specification of thepresent invention (for example, as a substituent of R² and R^(23a)above), it is to be understood that the groups of those substituents(R^(a), R^(b), R^(c), R^(d), and R^(e) in this example), areindependently, the same of different within each group and amoung thegroups.

In one embodiment, the compound has the followings stereostructure orits enantiomer:

wherein R¹ is alkenyl; R² is H; R³ is —CH₂CH(CH₃), CH₂CH₂, —CH═CH, or—CH═C(CH₃). In one such compound (16-desmethyldictyostatin), R³ isCH₂CH₂, R⁵ is OH, R¹ is CH═CH₂ and R^(23a), R^(23b) are H. In anotherembodiment, R⁵ is OH or OSiR^(a)R^(b)R^(c). In several embodiments,C2-C3 E-sterioisomers of the compounds or their enantiomers areprovided.

Several intermediates are useful in synthesizing such compounds. Forexample, one such intermediate is a compound of the following structureor its enantiomer.

wherein R¹ is H, an alkyl group, an aryl group, an alkenyl group, analkynyl group, or a halogen atom;R² and R^(2d) are independently H, a protecting group, an alkyl group, abenzyl group, a trityl group, —SiR^(a)R^(b)R^(c), CH₂OR^(d), or COR^(e);R^(a), R^(b) and R^(c) are independently an alkyl group or an arylgroup;R^(d) is an alkyl group, an aryl group, an alkoxylalkyl group,—R^(i)SiR^(a)R^(b)R^(c) or a benzyl group, wherein R^(i) is an alkylenegroup;R^(e) is an alkyl group, an allyl group, a benzyl group, an aryl group,an alkoxy group, or —NR^(g)R^(h) wherein R^(g) and R^(h) areindependently H, an alkyl group or an aryl group;R³ is (CH₂)_(n) where n is and integer in the range of 0 to 5,—CH₂CH(CH₃)—, —CH═CH—, —CH═C(CH₃)—, or —C≡C—;

R⁴ is

wherein R^(23a) is H, a protecting group, an alkyl group, a benzylgroup, a trityl group, —SiR^(a)R^(b)R^(c), CH₂OR^(d), or COR^(e),R^(23b) is H, a protecting group, an alkyl group, a benzyl group, atrityl group, —SiR^(a)R^(b)R^(c), CH₂OR^(d), or COR^(e), or R^(23a) andR^(23b) together form a portion of six-membered acetal ringincorporating CR^(t)R^(u);R^(t) and R^(u) are independently H, an alkyl group, an aryl group or analkoxyaryl group;R⁵ is H or OR^(2b), wherein R^(2b) is H, a protecting group, an alkylgroup, an aryl group, a benzyl group, a trityl group,—SiR^(a)R^(b)R^(c), CH₂OR^(d), or COR^(e); andR¹⁰ is H or alkyl.

In one embodiment, the compound has the following stereostructure, orits enantiomer:

wherein R¹ is alkenyl; R² is H; R^(2d) is H, OC(O)CH₃ orOC(O)NR^(g)R^(h) wherein R^(g) and R^(h) are independently H, an alkylgroup or an aryl group; R³ is CH₂CH(CH₃), CH₂CH₂, CH═CH or CH═C(CH₃);and R⁵ is OH or OSiR^(a)R^(b)R^(c); and R¹⁰ is H or alkyl. In oneembodiment, R¹ is —CH═CH₂, and R^(2d) is H, C(O)CH₃ or C(O)NH₂.

In another aspect, a compound of the following structure or itsenantiomer is provided:

wherein R¹ is H, an alkyl group, an aryl group, an alkenyl group, analkynyl group, or a halogen atom;R² and R^(2d) are independently H, a protecting group, an alkyl group, abenzyl group, a trityl group, —SiR^(a)R^(b)R^(c), CH₂OR^(d), or COR^(e);R^(a), R^(b) and R^(c) are independently an alkyl group or an arylgroup;R^(d) is an alkyl group, an aryl group, an alkoxylalkyl group,—R^(i)SiR^(a)R^(b)R^(c) or a benzyl group, wherein R^(i) is an alkylenegroup;R^(e) is an alkyl group, an allyl group, a benzyl group, an aryl group,an alkoxy group, or —NR^(g)R_(h), wherein R^(g) and R^(h) areindependently H, an alkyl group or an aryl group;R³ is (CH₂)_(n) where n is and integer in the range of 0 to 5,—CH₂CH(CH₃), —CH═CH—, —CH═C(CH₃), or —C≡C—;R⁵ is H or OR^(2b), wherein R^(2b) is H, a protecting group, an alkylgroup, an aryl group, a benzyl group, a trityl group,—SiR^(a)R^(b)R^(c), CH₂OR^(d), or COR^(e);R^(11a) and R^(11b) are independently H, an alkyl group, a benzyl group,a trityl group, —SiR^(a)R^(b)R^(c), CH₂OR^(d), COR^(e), or R^(11a) andR^(11b) together form a portion of six-membered acetal ringincorporating CR^(t)R^(u);R^(t) and R^(u) are independently H, an alkyl group, an aryl group or analkoxyaryl group; andR¹² is a halogen atom, CH₂OR^(2c), CHO, CO₂R¹⁰, CH═CHCH₂OR^(2c),CH═CHCHO, wherein R^(2c) is H, a protecting group, an alkyl group, abenzyl group, a trityl group, —SiR^(a)R^(b)R^(c), CH₂OR^(d), or COR^(e),and R¹⁰ is H or alkyl.

In one embodiment, the compound has the following stereostructure or itsenantiomer:

wherein R¹ is alkenyl; R² and R^(2d) are independently, H, OC(O)CH₃ orOC(O)NR^(g)R^(h) wherein R^(g) and R^(h) are independently H, an alkylgroup or an aryl group; R³ is CH₂CH(CH₃)CH₂CH₂, CH═CH or CH═C(CH₃);R^(11a) and R^(11b) are H or together form a portion of a six-memberedacetal ring containing C(H)(p-C₆H₄OCH₃) or C(CH₃)₂; R¹² is a halogenatom, CH₂OR^(2c), CHO, CO₂R¹⁰, CH═CHCH₂OR^(2c), CH═CHCHO, wherein R^(2c)is H, an alkyl group, a benzyl group, a trityl group,—SiR^(a)R^(b)R^(c), CH₂OR^(d), or COR^(e), and R¹⁰ is H or alkyl. In oneembodiment, R¹ is —CH═CH₂, R^(2d) is H, —C(O)CH₃ or —O(O)NH₂, and R¹² is—CH₂OH, —CHO or —CO₂R¹⁰.

In another aspect, a compound having the following stereostructure orits enantiomer is provided:

wherein R² is H, a protecting group, an alkyl group, a benzyl group, atrityl group, —SiR^(a)R^(b)R^(c), CH₂OR^(d), or COR^(e);R^(a), R^(b) and R^(c) are independently an alkyl group or an arylgroup;R^(d) is an alkyl group, an aryl group, an alkoxylalkyl group,—R^(i)SiR^(a)R^(b)R^(c) or a benzyl group, wherein R^(i) is an alkylenegroup;R^(e) is an alkyl group, an allyl group, a benzyl group, an aryl group,an alkoxy group, or —NR^(g)R^(h), wherein R^(g) and R^(h) areindependently H, an alkyl group or an aryl group;R³ is (CH₂)_(n) where n is and integer in the range of 0 to 5,—CH₂CH(CH₃), —CH═CH—, —CH═C(CH₃), or —C≡C—;R⁵ is H or OR^(2b), wherein R^(2b) is H, a protecting group, an alkylgroup, a benzyl group, a trityl group, —SiR^(a)R^(b)R^(c), CH₂OR^(d), orCOR^(e);R^(11a) and R^(11b) are independently H, a protecting group, an alkylgroup, a benzyl group, a trityl group, —SiR^(a)R^(b)R^(c), CH₂OR^(d),COR^(e), or R^(11a) and R^(11b) together form a portion of six-memberedacetal ring containing CR^(t)R^(u);R^(t) and R^(u) are independently H, an alkyl group, an aryl group or analkoxyaryl group;R¹² is a halogen atom, CH₂OR^(2c), CHO, CO₂R¹⁰, CH═CHCH₂OR^(2c) orCH═CHCHO, CH═CHCO₂R¹⁰, wherein R^(2c) is H, a protecting group, an alkylgroup, a benzyl group, a trityl group, —SiR^(a)R^(b)R^(c), CH₂OR^(d), orCOR^(e), and R¹⁰ is H or alkyl; andR^(14a) and R^(14b) are independently H, a protecting group, an alkylgroup, a benzyl group, a trityl group, —SiR^(a)R^(b)R^(c), CH₂OR^(d),COR^(e), or R^(14a) and R^(14b) together form a six-membered ringcontaining CR^(v)R^(w), wherein R^(v) and R^(w) are independently H, analkyl group, an aryl group or an alkoxyaryl group.

In one embodiment, the compound has the following stereostructure or itsenantiomer:

wherein R² is H; R³ is CH₂CH(CH₃) or CH═C(CH₃); R^(11a) and R^(11b) areH or together form a portion of a six-membered acetal ring containingC(H)(p-C₆H₄OCH₃) or C(CH₃)₂; R¹² is a halogen atom, CH₂OR^(2c), CHO,CO₂R¹⁰, CH═CHCH₂OR^(2c), CH═CHCHO or CH═CHCO₂R¹⁰, wherein R^(2c) is H,an alkyl group, an aryl group, a benzyl group, a trityl group,—SiR^(a)R^(b)R^(c), CH₂OR^(d), or COR^(e), and R¹⁰ is H or alkyl.

In another aspect, a compound having the following formula, or itsenantiomer is provided:

R² is H, a protecting group, an alkyl group, a benzyl group, a tritylgroup, —SiR^(a)R^(b)R^(c), CH₂OR^(d), or COR^(e);R^(a), R^(b) and R^(c) are independently an alkyl group or an arylgroup;R^(d) is an alkyl group, an aryl group, an alkoxylalkyl group,—R^(i)SiR^(a)R^(b)R^(c) or a benzyl group, wherein R^(i) is an alkylenegroup;R^(e) is an alkyl group, an allyl group, a benzyl group, an aryl group,an alkoxy group, or —NR^(g)R^(h), wherein R^(g) and R^(h) areindependently H, an alkyl group or an aryl group;R³ is (CH₂)_(n) where n is and integer in the range of 0 to 5,—CH₂CH(CH₃)—, —CH═CH—, —CH═C(CH₃)—, or —C≡C—;R^(11a) and R^(11b) are independently H, an alkyl group, a benzyl group,a trityl group, —SiR^(a)R^(b)R^(c), CH₂OR^(d), COR^(e), or R^(11a) andR^(11b) together form a portion of six-membered acetal ring containingCR^(t)R^(u);R^(t) and R^(u) are independently H, an alkyl group, an aryl group or analkoxyaryl group;R¹² is a halogen atom, CH₂OR^(2c), CHO, CO₂R¹⁰, CH═CHCH₂OR^(2c),CH═CHCHO or CH═CHCO₂R¹⁰, wherein R^(2c) is H, a protecting group, analkyl group, a benzyl group, a trityl group, —SiR^(a)R^(b)R^(c),CH₂OR^(d), or COR^(e), and R¹⁰ is H or alkyl; andR^(14a) and R^(14b) are independently H, a protecting group, an alkylgroup, a benzyl group, a trityl group, —SiR^(a)R^(b)R^(c), CH₂OR^(d),COR^(e), or R^(14a) and R^(14b) together form a six-membered ringcontaining CR^(v)R^(w), wherein R^(v) and R^(w) are independently H, analkyl group, an aryl group or an alkoxyaryl group.

In one embodiment, the compound has the following stereostructure or itsenantiomer:

wherein R³ is CH₂CH₂, CH═CH, CH₂CH(CH₃) or CH═C(CH₃); R¹² is a halogenatom, CH₂OR^(2c), CHO, CO₂R¹⁰, CH═CHCH₂OR^(2c), CH═CHCHO or CH═CHCO₂R¹⁰,wherein R^(2c) is H, an alkyl group, an aryl group, a benzyl group, atrityl group, —SiR^(a)R^(b)R^(c), CH₂OR^(d), or COR^(e), and R¹⁰ is H oralkyl.

In a further aspect, a compound having the following formula or itsenantiomer is provided:

wherein R² is H, a protecting group, an alkyl group, an aryl group, abenzyl group, a trityl group, —SiR^(a)R^(b)R^(c), CH₂OR^(d), or COR^(e);R^(a), R^(b) and R^(c) are independently an alkyl group or an arylgroup;R^(d) is an alkyl group, an aryl group, an alkoxylalkyl group,—R^(i)SiR^(a)R^(b)R^(c) or a benzyl group, wherein R^(i) is an alkylenegroup;R^(e) is an alkyl group, an allyl group, a benzyl group, an aryl group,an alkoxy group, or —NR^(g)R^(h), wherein R^(g) and R^(h) areindependently H, an alkyl group or an aryl group;R^(11a) and R^(11b) are independently H, an alkyl group, and aryl group,a benzyl group, a trityl group, —SiR^(a)R^(b)R^(c), CH₂OR^(d), COR^(e),or R^(11a) and R^(11b) together form a portion of six-membered acetalring containing CR^(t)R^(u);R^(t) and R^(u) are independently H, an alkyl group or an aryl group;R¹² is a halogen atom, CH₂OR^(2c), CHO, CO₂R¹⁰, CH═CHCH₂OR^(2c),CH═CHCHO or CH═CHCO₂R¹⁰, wherein R^(2c) is H, a protecting group, analkyl group, an aryl group, a benzyl group, a trityl group,—SiR^(a)R^(b)R^(c), CH₂OR^(d), or COR^(e), and R¹⁰ is H or alkyl;R⁶ is H or alkyl; andR¹⁷ is CH₂OR^(2f), CHO, CO₂R¹⁰, wherein R^(2f) is H, a protecting group,an alkyl group, an aryl group, a benzyl group, a trityl group,—SiR^(a)R^(b)R^(c), CH₂OR^(d), or COR^(e); andR²⁴ is C≡C, cis or trans CH═CH, or CH₂CH₂.

In one embodiment, the compound has the following stereostructure or itsenantiomer:

wherein R² is H, an alkyl group, a benzyl group, a trityl group,—SiR^(a)R^(b)R^(c), CH₂OR^(d), or COR^(e), and

R²⁴ is C≡C or cis CH═CH.

In one embodiment, a process for synthesizing dictyostatin analogsincludes a process for conversion of a first compound having thefollowing formula or its enantiomer:

wherein R¹ is H, an alkyl group, an aryl group, an alkenyl group, analkynyl group, or a halogen atom;R² is H, a protecting group, an alkyl group, a benzyl group, a tritylgroup, —SiR^(a)R^(b)R^(c), CH₂OR^(d), or COR^(e);

R^(2d) is H;

R^(a), R^(b) and R^(c) are independently an alkyl group or an arylgroup;R^(d) is an alkyl group, an aryl group, an alkoxylalkyl group,—R^(i)SiR^(a)R^(b)R^(c) or a benzyl group, wherein R^(i) is an alkylenegroup;R^(e) is an alkyl group, an allyl group, a benzyl group, an aryl group,an alkoxy group, or —NR^(g)R^(h), wherein R^(g) and R^(h) areindependently H, an alkyl group or an aryl group;R³ is (CH₂), where n is and integer in the range of 0 to 5,—CH₂CH(CH₃)—, —CH═CH—, —CH═C(CH₃)—, or —C≡C—;

R⁴ is

wherein R^(23a) is H, a protecting group, an alkyl group, a benzylgroup, a trityl group, —SiR^(a)R^(b)R^(c), CH₂OR^(d), or COR^(e),R^(23b) is H, a protecting group, an alkyl group, a benzyl group, atrityl group, —SiR^(a)R^(b)R^(c), CH₂OR^(d), or COR^(e), or R^(23a) andR^(23b) together form a portion of six-membered acetal ringincorporating CR^(t)R^(u);R^(t) and R^(u) are independently H, an alkyl group, an aryl group or analkoxyaryl group; and

R¹⁰ is H;

to a second compound with the formula

comprising the step of reacting the first compound under conditionssuitable to effect macrolactonization.

In one embodiment, the first compound has the following stereostructureor its enantiomer:

wherein R¹ is H, an alkyl group, an alkenyl group, an alkynyl group, ora halogen atom;R² is H, an alkyl group, a benzyl group, a trityl group,—SiR^(a)R^(b)R^(c), CH₂OR^(d), or COR^(e);

R^(2d) is H;

R^(a), R^(b) and R^(c) are independently an alkyl group or an arylgroup;R^(d) is an alkyl group, an aryl group, an alkoxylalkyl group,—R^(i)SiR^(a)R^(b)R^(c) or a benzyl group, wherein R^(i) is an alkylenegroup;R^(e) is an alkyl group, an allyl group, a benzyl group, an aryl group,an alkoxy group, or —NR^(g)R^(h) wherein R^(g) and R^(h) areindependently H, an alkyl group or an aryl group;R³ is (CH₂)_(n) where n is and integer in the range of 0 to 5,—CH₂CH(CH₃)—, —CH═CH—, —CH═C(CH₃)—, or —C≡C—; and

R¹⁰ is H;

and the second compound has the following formula or its enantiomer

In one embodiment, R¹ is alkenyl; R³ is CH₂CH₂, CH═CH, CH₂CH(CH₃) orCH═C(CH₃); and R⁵ is OR^(2b). In one embodiment of the process, thefirst compound is reacted with 2,4,6-trichlorobenzoylchloride.

In another aspect, the present invention provides a compound having thefollowing formula, or its enantiomer

R² is H, a protecting group, an alkyl group, a benzyl group, a tritylgroup, —SiR^(a)R^(b)R^(c), CH₂OR^(d), or COR^(e);R^(a), R^(b) and R^(c) are independently an alkyl group or an arylgroup;R^(d) is an alkyl group, an aryl group, an alkoxylalkyl group,—R^(i)SiR^(a)R^(b)R^(c) or a benzyl group, wherein R^(i) is an alkylenegroup;R^(e) is an alkyl group, an allyl group, a benzyl group, an aryl group,an alkoxy group, or —NR^(g)R^(h) wherein R^(g) and R^(h) areindependently H, an alkyl group or an aryl group;R³ is (CH₂)_(n) where n is and integer in the range of 0 to 5,—CH₂CH(CH₃)—, —CH═CH—, —CH═C(CH₃)—, or —C≡C—;R^(11a) and R^(11b) are independently H, a protecting group, an alkylgroup, a benzyl group, a trityl group, —SiR^(a)R^(b)R^(c), CH₂OR^(d),COR^(e), or R^(11a) and R^(11b) together form a portion of six-memberedacetal ring containing CR^(t)R^(u);R^(t) and R^(u) are independently H, an alkyl group, an aryl group or analkoxyaryl group;R¹² is a halogen atom, CH₂OR^(2c), CHO, CO₂R¹⁰, CH═CHCH₂OR^(2c),CH═CHCHO or CH═CHCO₂R¹⁰, wherein R^(2c) is H, a protecting group, analkyl group, an aryl group, a benzyl group, a trityl group,—SiR^(a)R^(b)R^(c), CH₂OR^(d), or COR^(e), and R¹⁰ is H or alkyl; andR^(14a) and R^(14b) are independently H, an alkyl group, a benzyl group,a trityl group, —SiR^(a)R^(b)R^(c), CH₂OR^(d), COR^(e), or R^(14a) andR^(14b) together form a six-membered ring containing CR^(v)R^(w),wherein R^(v) and R^(w) are independently H, an alkyl group, an arylgroup or an alkoxyaryl group.In one embodiment, the compound has the following stereostructure, orits enantiomer

wherein R³ is CH₂CH(CH₃)CH₂CH₂, CH═CH, or CH═C(CH₃); and R^(11a) andR^(11b) are H or together form a portion of a six-membered acetal ringcontaining C(H)(p-C₆H₄OCH₃) or C(CH₃)₂.In another aspect, the present invention provides a compound having thefollowing formula, or its enantiomer

wherein R² is H, a protecting group, an alkyl group, an aryl group, abenzyl group, a trityl group, —SiR^(a)R^(b)R^(c), CH₂OR^(d), or COR^(e);R^(a), R^(b) and R^(c) are independently an alkyl group or an arylgroup;R^(d) is an alkyl group, an aryl group, an alkoxylalkyl group,—R^(i)SiR^(a)R^(b)R^(c) or a benzyl group, wherein R^(i) is an alkylenegroup;R^(e) is an alkyl group, an allyl group, a benzyl group, an aryl group,an alkoxy group, or —NR^(g)R^(h), wherein R^(g) and R^(h) areindependently H, an alkyl group or an aryl group;R¹¹ is a protecting group, an alkyl group, and aryl group, a benzylgroup, a trityl group, —SiR^(a)R^(b)R^(c), CH₂OR^(d), or COR^(e);R¹² is a halogen atom, CH₂OR^(2c), CHO, CO₂R¹⁰, CH═CHCH₂OR^(2c),CH═CHCHO or CH═CHCO₂R¹⁰, wherein R^(2c) is H, a protecting group, analkyl group, an aryl group, a benzyl group, a trityl group,—SiR^(a)R^(b)R^(c), CH₂OR^(d), or COR^(e), and R¹⁰ is H or alkyl;R¹⁶ is H or alkyl;R¹⁷ is CH₂OR^(2f), CHO, CO₂R¹⁰, wherein R^(2f) is H, an alkyl group, anaryl group, a benzyl group, a trityl group, —SiR^(a)R^(b)R^(c),CH₂OR^(d), or COR^(e); andR²⁴ is C≡C, cis or trans CH═CH, or CH₂CH₂.

In one embodiment, the compound has the following stereostructure, orits enantiomer

wherein R² is H, an alkyl group, a benzyl group, a trityl group,—SiR^(a)R^(b)R^(c), CH₂OR^(d), or COR^(e); and

R²⁴ is C≡C or cis CH═CH.

In another aspect, the present invention provides a compound having thefollowing formula, or its enantiomer

wherein X is H, NCH₃(OCH₃), or a leaving group;R¹¹ is H, a protecting group, an alkyl group, and aryl group, a benzylgroup, a trityl group, —SiR^(a)R^(b)R^(c), CH₂OR^(d), or COR^(e),R^(t) and R^(u) are independently H, an alkyl group or an aryl group;R¹² is a halogen atom, CH₂OR^(2c), CHO, CO₂R¹⁰, CH═CHCH₂OR^(2c),CH═CHCHO or CH═CHCO₂R¹⁰, wherein R^(2c) is H, a protecting group, analkyl group, an aryl group, a benzyl group, a trityl group,—SiR^(a)R^(b)R^(c), CH₂OR^(d), or COR^(e), and R¹⁰ is H or alkyl.

In a further aspect, the present invention provides a compound havingthe following formula, or its enantiomer

wherein R^(11a) and R^(11b) are independently H, a protecting group, analkyl group, and aryl group, a benzyl group, a trityl group,—SiR^(a)R^(b)R^(c), CH₂OR^(d), COR^(e), or R^(11a) and R^(11b) togetherform a portion of six-membered acetal ring containing CR^(t)R^(u);R^(t) and R^(u) are independently H, an alkyl group, an aryl group or analkoxyaryl group;R¹² is a halogen atom, CH₂OR^(2c), CHO, CO₂R¹⁰, CH═CHCH₂OR^(2c),CH═CHCHO or CH═CHCO₂R¹⁰, wherein R^(2c) is H, a protecting group, analkyl group, an aryl group, a benzyl group, a trityl group,—SiR^(a)R^(b)R^(c), CH₂OR^(d), or COR^(e), and R¹⁰ is H or alkyl;

In another aspect, the present invention provides a process ofconversion of a compound with the following formula, or its enantiomer

wherein R² protecting group, an alkyl group, an aryl group, a benzylgroup, a trityl group, —SiR^(a)R^(b)R^(c), CH₂OR^(d), or COR^(e);R^(a), R^(b) and R^(c) are independently an alkyl group or an arylgroup;R^(d) is an alkyl group, an aryl group, an alkoxylalkyl group,—R^(i)SiR^(a)R^(b)R^(c) or a benzyl group, wherein R^(i) is an alkylenegroup;R^(e) is an alkyl group, an allyl group, a benzyl group, an aryl group,an alkoxy group, or —NR^(g)R^(h), wherein R^(g) and R^(h) areindependently H, an alkyl group or an aryl group;R^(11b′) is an alkyl group, and aryl group, a benzyl group, a tritylgroup, —SiR^(a)R^(b)R^(c), CH₂OR^(d), COR^(e);R¹² is a halogen atom, CH₂OR^(2c), CO₂R¹⁰, CH═CHCH₂OR^(2c), orCH═CHCO₂R¹⁰, wherein R^(2c) is a protecting group, an alkyl group, anaryl group, a benzyl group, a trityl group, —SiR^(a)R^(b)R^(c),CH₂OR^(d), or COR^(e), and R¹⁰ is H or alkyl;R¹⁶ is H or alkyl; andR¹⁷ is CH₂OR^(2f), CO₂R¹⁰, wherein R^(2f) is H, a protecting group, analkyl group, an aryl group, a benzyl group, a trityl group,—SiR^(a)R^(b)R^(c), CH₂OR^(d), or COR^(e); andR²⁴ is C≡C to a compound of the following formula, or its enantiomer

wherein R^(11a) is H, an alkyl group, and aryl group, a benzyl group, atrityl group, —SiR^(a)R^(b)R^(c), CH₂OR^(d), COR^(e) and R^(11b) is analkyl group, and aryl group, a benzyl group, a trityl group,—SiR^(a)R^(b)R^(c), CH₂OR^(e), COR^(e), or R^(11a) and R^(11b) togetherform a portion of six-membered acetal ring containing CR^(t)R^(u);R^(t) and R^(u) are independently H, an alkyl group or an aryl group;andR²⁴ is cis CH═CH, including at least the steps of semi-reduction of thealkyne and asymmetric reduction of the ketone, or asymmetric reductionof the ketone and semihydrogentation of the alkyne.

In one embodiment, the process includes at least the steps ofsemi-reduction of the alkyne, asymmetric reduction of the ketone andprotection of a resulting alcohol, or asymmetric reduction of theketone, protection of a resulting alcohol and semihydrogentation of thealkyne, or asymmetric reduction of the ketone, semi-hydrogentation ofthe alkyne and protection of a resulting alcohol.

In a further aspect, the present invention provides a compound of thefollowing formula, or its enantiomer

wherein R² is H, a protecting group, an alkyl group, an aryl group, abenzyl group, a trityl group, SiR^(a)R^(b)R^(c), CH₂OR^(d), or COR^(e);R^(a), R^(b) and R^(c) are independently an alkyl group or an arylgroup;R^(d) is an alkyl group, an aryl group, an alkoxylalkyl group,—R^(i)SiR^(a)R^(b)R^(c) or a benzyl group, wherein R^(i) is an alkylenegroup;R^(e) is an alkyl group, an allyl group, a benzyl group, an aryl group,an alkoxy group, or —NR^(g)R^(h), wherein R^(g) and R^(h) areindependently H, an alkyl group or an aryl group;R¹⁶ is H or alkyl; andR¹⁷ is CH₂OR^(2f), CHO, CONHCH(CH₃)CH(OH)Ph, CO₂R¹⁰, wherein R^(2f) isH, a protecting group, an alkyl group, an aryl group, a benzyl group, atrityl group, —SiR^(a)R^(b)R^(c), CH₂OR^(d), or COR^(e);

R²⁵ is CO₂R¹⁰, CHO, CH═CBr₂, C≡CH, or C≡C SiR^(a)R^(b)R^(c); and

R¹⁰ is H or an alkyl group.

In another aspect the present invention provides a process for reactinga first compound of the following formula, or its enantiomer

wherein R^(2a) protecting group, an alkyl group, an aryl group, a benzylgroup, a trityl group, —SiR^(a)R^(b)R^(c), CH₂OR^(d), or COR^(e);R^(a), R^(b) and R^(c) are independently an alkyl group or an arylgroup;R^(d) is an alkyl group, an aryl group, an alkoxylalkyl group,—R^(i)SiR^(a)R^(b)R^(c) or a benzyl group, wherein R^(i) is an alkylenegroup;R^(e) is an alkyl group, an allyl group, a benzyl group, an aryl group,an alkoxy group, or —NR^(g)R^(h), wherein R^(g) and R^(h) areindependently H, an alkyl group or an aryl group;R¹⁶ is H or alkyl; andR¹⁷ is CH₂OR^(2f), CHO, CO₂R^(v), wherein R^(2f) is H, an alkyl group,an aryl group, a benzyl group, a trityl group, —SiR^(a)R^(b)R^(c),CH₂OR^(d), or COR^(e);

R²⁵CH═CX₂, C≡CH or C≡CSiR^(a)R^(b)R;

X is Cl, Br or I with a second compound of the following formula, or itsenantiomer

wherein X is NCH₃(OCH₃), or a leaving group;R¹¹ an alkyl group, and aryl group, a benzyl group, a trityl group,—SiR^(a)R^(b)R^(c), CH₂OR^(d), COR^(e);R¹² is a halogen atom, CH₂OR^(2c), CO₂R^(v), CH═CHCH₂OR^(2c) orCH═CHCO₂R^(v), wherein R^(2c) is an alkyl group, an aryl group, a benzylgroup, a trityl group, —SiR^(a)R^(b)R^(c), CH₂OR^(d), or COR^(e), andR^(v) is alkyl, including the steps of metalation of the first compoundand addition of the second compound to produce a compound of thefollowing formula, or its enantiomer

wherein R²⁴ is C≡C.

In another aspect, the present invention provides a process for reactinga first compound of the following formula, or its enantiomer

wherein R² a protecting group, an alkyl group, an aryl group, a benzylgroup, a trityl group, —SiR^(a)R^(b)R^(c), CH₂OR^(d), or COR^(e);R^(a), R^(b) and R^(c) are independently an alkyl group or an arylgroup;R^(d) is an alkyl group, an aryl group, an alkoxylalkyl group,—R^(i)SiR^(a)R^(b)R^(c) or a benzyl group, wherein R^(i) is an alkylenegroup;R^(e) is an alkyl group, an allyl group, a benzyl group, an aryl group,an alkoxy group, or —NR^(g)R^(h) wherein R^(g) and R^(h) areindependently H, an alkyl group or an aryl group;R¹⁶ is H or alkyl;R¹⁷ is CH₂OR^(2f), CHO, CO₂R¹⁰, wherein R^(2f) is H, an alkyl group, anaryl group, a benzyl group, a trityl group, —SiR^(a)R^(b)R^(c),CH₂OR^(d), or COR^(e);

R²⁵CH═CX₂, C≡CH or C≡CSiR^(a)R^(b)R;

with a second compound of the following formula, or its enantiomer

wherein X is H;R¹¹ an alkyl group, and aryl group, a benzyl group, a trityl group,—SiR^(a)R^(b)R^(c), CH₂OR^(d), COR^(e);R¹² is a halogen atom, CH₂OR^(2c), CO₂R¹⁰, CH═CHCH₂OR^(2c) orCH═CHCO₂R¹⁰, wherein R^(2c) is an alkyl group, an aryl group, a benzylgroup, a trityl group, —SiR^(a)R^(b)R^(c), CH₂OR^(d), or COR^(e), andR¹⁰ is alkyl, including the steps of metalation of the first compoundand addition of the second compound to produce a compound of thefollowing formula, or its enantiomer

wherein R²⁴ is C≡C.

In another aspect, the present invention provides a compound of thefollowing structure

wherein R¹ is H, an alkyl group, an aryl group, an alkenyl group, analkynyl group, or a halogen atom;R² is H, a protecting group, an alkyl group, a benzyl group, a tritylgroup, —SiR^(a)R^(b)R^(c), CH₂OR^(d), or COR^(e);R^(a), R^(b) and R^(c) are independently an alkyl group or an arylgroup;R^(d) is an alkyl group, an aryl group, an alkoxylalkyl group,—R^(i)SiR^(a)R^(b)R^(c) or a benzyl group, wherein R^(i) is an alkylenegroup;R^(e) is an alkyl group, an allyl group, a benzyl group, an aryl group,an alkoxy group, or —NR^(g)R^(h), wherein R^(g) and R^(h) areindependently H, an alkyl group or an aryl group;R³ is (CH₂), where n is and integer in the range of 0 to 5, —CH₂CH(CH₃),—CH═CH—, —CH═C(CH₃), or —C≡C—;R⁴ is (CH₂)_(p) where p is an integer in the range of 4 to 12,—(CHR^(k1))_(y1)(CHR^(k2))_(y2)(CHR^(k3))_(k3)(CHR^(k4))_(y4)(CHR^(k5))_(y5)C(R^(s1))═C(R^(s2))C(R^(s3))═C(R^(s4))—,—(CHR^(k1))_(y1)(CHR^(k2))_(y2)(CHR^(k3))_(y3)(CHR^(k4))_(y4)(CHR^(k5))_(y5)CH(R^(s1))CH(R^(s2))C(R^(s3))═C(R^(s4)),—(CH^(k1))_(y1)(CHR^(k2))_(y2)(CHR^(k3))_(y3)(CHR^(k4))_(y4)(CHR^(k5))_(y5)C(R^(s2))═C(R^(s2))CH(R^(s3))CH(R^(s4))—,(CHR^(k1))_(y1)(CHR^(k2))_(y2)(CHR^(k3))_(y3)(CHR^(k4))_(y4)(CHR^(k5))_(y5)CH(R^(s1))CH(R^(s2))CH(R^(s3))CH(R^(s4)),whereiny1 and y2 are 1 and y3, y4 and y5 are independently 0 or 1, R^(k1),R^(k2), R^(k3), R^(k4) and R^(k5) are independently H, CH₃, or OR^(2a),and R^(s1), R^(s2), R^(s3), and R^(s4) are independently H or CH₃,whereinR^(2a) is H, a protecting group, an alkyl group, a benzyl group, atrityl group, —SiR^(a)R^(b)R^(c), CH₂OR^(d), or COR^(e); andR⁵ is H or OR^(2b), wherein R^(2b) is H, a protecting group, an alkylgroup, an aryl group, a benzyl group, a trityl group,—SiR^(a)R^(b)R^(c), CH₂OR^(d), or COR^(e); andR²⁶ is H, a protecting group, an alkyl group, an aryl group,—SiR^(a)R^(b)R^(c), or COR^(e);

In one embodiment, the compound of has the following stereostructure, orits enantiomer

wherein R¹ is alkenyl; R³ is —CH₂CH₂, —CH═CH, —CH₂CH(CH₃) or —CH═C(CH₃);and R⁴ is

wherein R^(23a) is H, a protecting group, an alkyl group, a benzylgroup, a trityl group, —SiR^(a)R^(b)R^(c), CH₂OR^(d), or COR^(e),R^(23b) is H, a protecting group, an alkyl group, a benzyl group, atrityl group, —SiR^(a)R^(b)R^(c), CH₂OR^(d), or COR^(e), or R^(23a) andR^(23b) together form a portion of six-membered acetal ringincorporating CR^(t)R^(u);R^(t) and R^(u) are independently H, an alkyl group, an aryl group or analkoxyaryl group.

In another aspect, the present invention provides a compound of thefollowing structure

wherein R¹ is H, an alkyl group, an aryl group, an alkenyl group, analkynyl group, or a halogen atom;R² is H, a protecting group, an alkyl group, a benzyl group, a tritylgroup, —SiR^(a)R^(b)R^(c), CH₂OR^(d), or COR^(e);R^(a), R^(b) and R^(c) are independently an alkyl group or an arylgroup;R^(d) is an alkyl group, an aryl group, an alkoxylalkyl group,—R^(i)SiR^(a)R^(b)R^(c) or a benzyl group, wherein R^(i) is an alkylenegroup;R^(e) is an alkyl group, an allyl group, a benzyl group, an aryl group,an alkoxy group, or —NR^(g)R^(h), wherein R^(g) and R^(h) areindependently H, an alkyl group or an aryl group;R³ is (CH₂)_(n) where n is and integer in the range of 0 to 5,—CH₂CH(CH₃)—, —CH═CH—, —CH═C(CH₃, or —C≡C—;R⁴ is (CH₂)_(p) where p is an integer in the range of 4 to 12,—(CHR^(k1))_(y1)(CHR^(k2))_(y2)(CHR^(k3))_(y3)(CHR^(k4))_(y4)(CHR^(k5))_(y5)C(R^(s1))═C(R^(s2))C(R^(s3))═C(R^(s4))—,—(CHR^(k1))_(y1)(CHR^(k2))_(y2)(CHR^(k3))_(y3)(CHR^(k4))_(y4)(CHR^(k5))_(y5)CH(R^(s1))CH(R^(s2))C(R^(s3))═C(R^(s4))—,—(CHR^(k1))_(y1)(CHR^(k2))_(y2)(CHR^(k3))_(y3)(CHR^(k4))_(y4)(CHR^(k5))_(y5)C(R^(s1))═C(R^(s2))CH(R^(s3))CH(R^(s4))—,—(CHR^(k1))_(y1)(CHR^(k2))_(y2)(CHR^(k3))_(y3)(CHR^(k4))_(y4)(CHR^(k5))_(y5)CH(R^(s1))CH(R^(s2))CH(R^(s3))CH(R^(s4))whereiny1 and y2 are 1 and y3, y4 and y5 are independently 0 or 1, R^(k1),R^(k2), R^(k3), R^(k4) and R^(k5) are independently H, CH₃, or OR^(2a),and R^(s1), R^(s2), R^(s3), and R^(s4) are independently H or CH₃,whereinR^(2a) is H, an alkyl group, a benzyl group, a trityl group,—SiR^(a)R^(b)R^(c), CH₂OR^(d), or COR^(e); andR⁵ is H or OR^(2b), wherein R^(2b) is H, a protecting group, an alkylgroup, an aryl group, a benzyl group, a trityl group,—SiR^(a)R^(b)R^(c), CH₂OR^(d), or COR^(e); andR²⁶ is H, a protecting group, an alkyl group, an aryl group,—SiR^(a)R^(b)R^(c), or COR^(e);

In one embodiment, the compound has the following stereostructure, orits enantiomer

wherein R¹ is alkenyl; R³ is —CH₂CH₂, —CH═CH, —CH₂CH(CH₃) or —CH═C(CH₃);and R⁴ is

wherein R^(23a) is H, a protecting group, an alkyl group, a benzylgroup, a trityl group, —SiR^(a)R^(b)R^(c), CH₂OR^(d), or CORE, R^(23b)is H, a protecting group, an alkyl group, a benzyl group, a tritylgroup, —SiR^(a)R^(b)R^(c), CH₂OR^(d), or COR^(e), or R^(23a) and R^(23b)together form a portion of six-membered acetal ring incorporatingCR^(t)R^(u);R^(t) and R^(u) are independently H, an alkyl group, an aryl group or analkoxyaryl group

In another aspect, the present invention provides a process forsynthesizing a compound having the following structure

wherein R¹ is H, an alkyl group, an aryl group, an alkenyl group, analkynyl group, or a halogen atom;R² is H, a protecting group, an alkyl group, a benzyl group, a tritylgroup, —SiR^(a)R^(b)R^(c), CH₂OR^(d), or COR^(e);R^(a), R^(b) and R^(c) are independently an alkyl group or an arylgroup;R^(d) is an alkyl group, an aryl group, an alkoxylalkyl group,—R^(i)SiR^(a)R^(b)R^(c) or a benzyl group, wherein R^(i) is an alkylenegroup;R^(e) is an alkyl group, an allyl group, a benzyl group, an aryl group,an alkoxy group, or —NR^(g)R^(h), wherein R^(g) and R^(h) areindependently H, an alkyl group or an aryl group;R³ is (CH₂), where n is and integer in the range of 0 to 5,—CH₂CH(CH₃)—, —CH═CH—, —CH═C(CH₃), or —C≡C—;R⁴ is (CH₂)_(p) where p is an integer in the range of 4 to 12,(CHR^(k1))_(y1)(CHR^(k2))_(y2)(CHR^(k3))_(y3)(CHR^(k4))_(y4)(CHR^(k5))_(k5)C(R^(s1))═C(R^(s2))C(R^(s3))═C(R^(s4))—,—(CHR^(k1))_(y1)(CHR^(k2))_(k2)(CHR^(k3))_(y3)(CHR^(k4))_(y4)(CHR^(k5))_(y5)CH(R^(s1))CH(R^(s2))C(R^(S3))═C(R^(s4)),—(CHR^(k1))_(y1)(CHR^(k2))_(y2)(CHR^(k3))_(y3)(CHR^(k4))_(y4)(CHR^(k5))_(y5)C(R^(s1))═C(R^(s2))CH(R^(s3))CH(R^(s4))—,—(CHR^(k1))_(y1)(CHR^(k2))_(y2)(CHR^(k3))_(y3)(CH^(k4))_(y4)(CH^(k5))_(y5)CH(R^(s1))CH(R^(s2))CH(R^(s3))CH(R^(s4))wherein y1 and y2 are 1 and y3, y4 and y5 are independently 0 or 1,R^(k1), R^(k2), R^(k3), R^(k4) and R^(k5) are independently H, CH₃, orOR^(2a), and R^(s1), R^(s2), R^(s3), and R^(s4) are independently H orCH₃, whereinR^(2a) is H, an alkyl group, a benzyl group, a trityl group,—SiR^(a)R^(b)R^(c), CH₂OR^(d), or COR^(e); andR⁵ is H or OR^(2b), wherein R^(2b) is H, an alkyl group, an aryl group,a benzyl group, a trityl group, —SiR^(a)R^(b)R^(c), CH₂OR^(d), orCOR^(e); andR²⁶ is H, a protecting group, an alkyl group, a aryl group,—SiR^(a)R^(b)R^(c), or COR^(e); including the step of reacting astarting compound having the formula:

wherein R¹⁰ is H, under conditions suitable to form the macrolactamring.

In one embodiment of the process, the starting compound has thefollowing structure, or its enantiomer

wherein R¹ is alkenyl; R³ is —CH₂CH(CH₃) or —CH═C(CH₃); and R⁴ is

wherein R^(23a) is H, a protecting group, an alkyl group, a benzylgroup, a trityl group, —SiR^(a)R^(b)R^(c), CH₂OR^(d), or COR^(e),R^(23b) is H, a protecting group, an alkyl group, a benzyl group, atrityl group, —SiR^(a)R^(b)R^(c), CH₂OR^(d), or COR^(e), or R^(23a) andR^(23b) together form a portion of six-membered acetal ringincorporating CR^(t)R^(u);R^(t) and R^(u) are independently H, an alkyl group, an aryl group or analkoxyaryl group and the product compound has the following structure,or its enantiomer

In a further aspect, the present invention provides a process forconverting a starting compound of the following structure

wherein R¹ is H, an alkyl group, an aryl group, an alkenyl group, analkynyl group, or a halogen atom;R² and R^(2d) are independently H, a protecting group, an alkyl group, abenzyl group, a trityl group, —SiR^(a)R^(b)R^(c), CH₂OR^(d), or COR^(e);R^(a), R^(b) and R^(c) are independently an alkyl group or an arylgroup;R^(d) is an alkyl group, an aryl group, an alkoxylalkyl group,—R^(i)SiR^(a)R^(b)R^(c) or a benzyl group, wherein R^(i) is an alkylenegroup;R^(e) is an alkyl group, an allyl group, a benzyl group, an aryl group,an alkoxy group, or —NR^(g)R^(h), wherein R^(g) and R^(h) areindependently H, an alkyl group or an aryl group;R³ is (CH₂), where n is and integer in the range of 0 to 5, —CH₂CH(CH₃),—CH═CH—, —CH═C(CH₃)—, or —C≡C—;R⁴ is (CH₂)_(p) where p is an integer in the range of 4 to 12,—(CHR^(k1))_(y1)(CHR^(k2))_(y2)(CHR^(k3))_(y3)(CHR^(k4))_(y4)(CHR^(k5))_(y5)C(R^(s1))═C(R^(s2))C(R^(s3))═C(R^(s4))—,—(CHR^(k1))_(y1)(CHR^(k2))_(k2)(CHR^(k3))_(y3)(CHR^(k4))_(y4)(CHR^(k5))_(y5)CH(R^(s1))CH(R^(s2))C(R^(s3))═C(R^(s4))—,—(CHR^(k1))_(y1)(CHR^(k2))_(y2)(CHR^(k3))_(y3)(CHR^(k4))_(y4)(CHR^(k5))_(y5)C(R^(s1))═C(R^(s2))CH(R^(s3))CH(R^(s4))—,—(CHR^(k1))_(y1)(CHR^(k2))_(y2)(CHR^(k3))_(y3)(CHR^(k4))_(y4)(CHR^(k5))_(y5)CH(R^(s1))CH(R^(s2))CH(R^(s3))CH(R^(s4))—,whereiny1 and y2 are 1 and y3, y4 and y5 are independently 0 or 1, R^(k1),R^(k2), R^(k3), R^(k4) and R^(k5) are independently H, —CH₃, or OR^(2a),and R^(s1), R^(s2), R^(s3), and R^(s4) are independently H or CH₃,whereinR⁵ is H, an alkyl group, an aryl group, a benzyl group, a trityl group,—SiR^(a)R^(b)R^(c), CH₂OR^(d), or COR^(e); andR⁵ is H or OR^(2b), wherein R_(2b) is H, a protecting group an alkylgroup, an aryl group, a benzyl group, a trityl group,—SiR^(a)R^(b)R^(c), CH₂OR^(d), or COR^(e); andR¹⁰ is H or alkyl to a compound of the following structure

where R²⁶ is H, a protecting group, an alkyl group, a aryl group,—SiR^(a)R^(b)R^(c), or COR^(e), including at least the steps of alcoholoxidation and reductive amination.

In one embodiment of the process, the starting compound has thefollowing structure, or its enantiomer

wherein R¹ is alkenyl; R³ is —CH₂CH(CH₃) or —CH═C(CH₃); and R⁴ is

wherein R^(23a) is H, a protecting group, an alkyl group, a benzylgroup, a trityl group, —SiR^(a)R^(b)R^(c), CH₂OR^(d), or COR^(e),R^(23b) is H, a protecting group, an alkyl group, a benzyl group, atrityl group, SiR^(a)R^(b)R^(c), CH₂OR^(d), or COR^(e), or R^(23a) andR^(23b) together form a portion of six-membered acetal ringincorporating CR^(t)R^(u);R^(t) and R^(u) are independently H, an alkyl group, an aryl group or analkoxyaryl group and the product compound has the following structure,or its enantiomer

In a further aspect, the present invention provides a compound of thefollowing structure or its enantiomer

wherein R¹ is H, a protecting group, an alkyl group, an aryl group, analkenyl group, an alkynyl group, or a halogen atom;R² and R^(2d) are independently H, a protecting group, an alkyl group, abenzyl group, a trityl group, SiR^(a)R^(b)R^(c), CH₂OR^(d), or COR^(e);R^(a), R^(b) and R^(c) are independently an alkyl group or an arylgroup;R^(d) is an alkyl group, an aryl group, an alkoxylalkyl group,—R^(i)SiR^(a)R^(b)R^(c) or a benzyl group, wherein R^(i) is an alkylenegroup;R^(e) is an alkyl group, an allyl group, a benzyl group, an aryl group,an alkoxy group, or —NR^(g)R^(h), wherein R^(g) and R^(h) areindependently H, an alkyl group or an aryl group;R³ is (CH₂)_(n) where n is and integer in the range of 0 to 5,—CH₂CH(CH₃)—, —CH═CH—, —CH═C(CH₃)—, or —C≡C—;

R⁴ is

wherein R^(23a) is H, a protecting group, an alkyl group, a benzylgroup, a trityl group, —SiR^(a)R^(b)R^(c), CH₂OR^(d), or CORE, R^(13b)is H, a protecting group, an alkyl group, a benzyl group, a tritylgroup, —SiR^(a)R^(b)R^(c), CH₂OR^(d), or COR^(e), or R^(23a) and R^(23b)together form a portion of six-membered acetal ring incorporatingCR^(t)R^(u);R^(t) and R^(u) are independently H, an alkyl group, an aryl group or analkoxyaryl group;R⁵ is H or OR^(2b), wherein R^(2b) is H, a protecting group, an alkylgroup, an aryl group, a benzyl group, a trityl group,—SiR^(a)R^(b)R^(c), CH₂OR^(d), or COR^(e);R¹⁰ is H or alkyl; and

R²⁷ is CH═CHC(O), CH═CHCH(OH), or CH₂CH₂C(O).

In still a further aspect, the present invention provides a compound ofthe following structure or its enantiomer

wherein R¹ is H, a protecting group, an alkyl group, an aryl group, analkenyl group, an alkynyl group, or a halogen atom;R² and R^(2d) are independently H, a protecting group, an alkyl group, abenzyl group, a trityl group, —SiR^(a)R^(b)R^(c), CH₂OR^(d), or COR^(e);R^(a), R^(b) and R^(c) are independently an alkyl group or an arylgroup;R^(d) is an alkyl group, an aryl group, an alkoxylalkyl group,—R^(i)SiR^(a)R^(b)R^(c) or a benzyl group, wherein R^(i) is an alkylenegroup;R^(e) is an alkyl group, an allyl group, a benzyl group, an aryl group,an alkoxy group, or —NR^(g)R^(h), wherein R^(g) and R^(h) areindependently H, an alkyl group or an aryl group;R³ is (CH₂)_(n) where n is and integer in the range of 0 to 5,—CH₂CH(CH₃)—, —CH═CH—, —CH═C(CH₃)—, or —C≡C—;R⁵ is H or OR^(2b), wherein R^(2b) is H, an alkyl group, an aryl group,a benzyl group, a trityl group, —SiR^(a)R^(b)R^(c), CH₂OR^(d), orCOR^(e);R^(11a) and R^(11b) are independently H, a protecting group, an alkylgroup, a benzyl group, a trityl group, —SiR^(a)R^(b)R^(c), CH₂OR^(d),COR^(e), or R^(11a) and R^(11b) together form a portion of six-memberedacetal ring incorporating CR^(t)R^(u);R^(t) and R^(u) are independently H, an alkyl group, an aryl group or analkoxyaryl group;R¹² is a halogen atom, CH₂OR^(2c), CHO, CO₂R¹⁰, CH═CHCH₂OR^(2c),CH═CHCHO, wherein R^(2c) is H, an alkyl group, a benzyl group, a tritylgroup, —SiR^(a)R^(b)R^(c), CH₂OR^(d), or COR^(e), and R¹⁰ is H or alkyl;and

R²⁷ is CH═CHC(O), CH═CHCH(OH), or CH₂CH₂C(O).

The above general structures for the compounds of the present inventioninclude all stereoisomers thereof (other than the natural compounddictyostatin 1). Moreover, the structures of the compounds of thepresent invention include the compounds in racemic form,enantiomerically enriched form or enantiomerically pure form. Whereindouble bonds (for example, with the groups —CH═CH— or —CH═C(CH₃)—) apresent in R³, a preferred stereoisomer is Z.

The terms “alkyl”, “aryl” and other groups refer generally to bothunsubstituted and substituted groups unless specified to the contrary.In that regard, the groups set forth above can be substituted with awide variety of substituents to synthesize analogs retaining biologicalactivity. Unless otherwise specified, alkyl groups are hydrocarbongroups and are preferably C₁-C₁₅ (that is, having 1 to 15 carbon atoms)alkyl groups, and more preferably C₁-C₁₀ alkyl groups, and can bebranched or unbranched, acyclic or cyclic. The above definition of analkyl group and other definitions apply also when the group is asubstituent on another group (for example, an alkyl group as asubstituent of an alkylamino group or a dialkylamino group). The term“aryl” refers to phenyl or naphthyl. As used herein, the terms “halogen”or “halo” refer to fluoro, chloro, bromo and iodo.

The term “alkoxy” refers to —OR, wherein R is an alkyl group. The term“alkenyl” refers to a straight or branched chain hydrocarbon group withat least one double bond, preferably with 2-15 carbon atoms, and morepreferably with 2-10 carbon atoms (for example, —CH═CHR or —CH₂CH═CHR;wherein R can be a group including, but not limited to, an alkyl group,an alkoxyalkyl group, an amino alkyl group, an aryl group, or a benzylgroup). The term “alkynyl” refers to a straight or branched chainhydrocarbon group with at least one triple bond, preferably with 2-15carbon atoms, and more preferably with 2-10 carbon atoms (for example,—C≡CR or —CH₂—C≡CR; wherein R can be a group including, but not limitedto, an alkyl group, an alkoxyalkyl group, an amino alkyl group, an arylgroup, or a benzyl group). The terms “alkylene,” “alkenylene” and“alkynylene” refer to bivalent forms of alkyl, alkenyl and alkynylgroups, respectively.

The term “trityl” refers to a triphenyl methyl group or —C(Ph)₃.

Certain groups such as amino and hydroxy groups may include protectivegroups as known in the art. Preferred protective groups for amino groupsinclude tert-butyloxycarbonyl, formyl, acetyl, benzyl,p-methoxybenzyloxycarbonyl, trityl. Preferred protecting groups foralcohol include trialkylsilyl (for example, triethylsilyl,triisopropylsilyl and tributyldimethylsilyl), p-methoxybenzyl, trityl,and (in the case of 1,3-diols) p-methoxyphenyl acetals. Other suitableprotecting groups as known to those skilled in the art are disclosed inGreene, T., Wuts, P. G. M., Protective Groups in Organic Synthesis,Wiley (1991), the disclosure of which is incorporated herein byreference.

Other aspects of the present invention include the synthesis of thecompounds of the present invention as well as the biological assaying ofsuch compounds and the biological activity of such compounds against,for example, cancer (such as breast, prostate cancer and ovariancancer). For example, in another aspect, the present invention providesa method of treating a patient for cancer, including the step ofadministering a pharmaceutically effective amount of a biologicallyactive compound of the present invention or a pharmaceuticallyacceptable salt thereof.

The present invention, along with the attributes and attendantadvantages thereof, will best be appreciated and understood in view ofthe following detailed description taken in conjunction with theaccompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates two embodiments of the synthesis of dictyostatinbottom fragment 15.

FIG. 2 illustrates two embodiments of the syntheses of dictyostatinmiddle fragment 29.

FIG. 3 illustrates one embodiment of the coupling of bottom and middlefragments of dictyostatin and elaboration to build the upper fragment.

FIG. 4 illustrates one embodiment of the construction of dictyostatin 1and representative analogs 50 and 59.

FIG. 5 illustrates an embodiment of the synthesis of representativeanalog C16-desmethyldictyostatin 79.

FIG. 6 illustrates an embodiment of the synthesis representative C6-epi,C14-epi intermediate 95.

FIG. 7 illustrates an embodiment of the synthesis of representativeanalog C2-E,C6-epi, C14-epi dictyostatin 100 and its C₂-C₃ Z-isomer.

FIG. 8 illustrates an embodiment of the synthesis of representativeanalog C6-epi, C14-ep, C19-epi dictyostatin 108 and its C₂-C₃ E-isomer.

FIG. 9 illustrates representative examples and methods of synthesis oflactam analogs of the present invention.

FIG. 10 illustrates representative turbidity profiles of16-desmethyldictyostatin in comparison to that of dictyostatin 1 in atubulin-only (no MAPs, no GTP, assembly supported by monosodiumglutamate) assay.

DETAILED DESCRIPTION OF THE INVENTION

FIGS. 1-9 show exemplary synthetic pathways and intermediates for thesynthesis of dictyostatin analogs.

The synthesis of an exemplary “bottom fragment” 15 for makingdictyostatin and analogs is shown in FIG. 1. 1,3-Propanediol 3 waselaborated via Evans chiral auxiliary-based methods to the known,bis-TBS-protected Horner-Wadsworth-Emmons product 10 in nine steps. See,Phukan, P.; Sasmal, S.; Maier, M. E. Eur. J. Org. Chem. 2003, 1733, andAndrus, M. B.; Argade, A. B. Tetrahedron Lett. 1996, 37, 5049. Thisunsaturated ester was reduced to the allylic alcohol 11, which wasprotected with a trityl group and its primary TBS group removed withHF-pyridine to give alcohol 13, which was oxidized in two steps to thecarboxylic acid and coupled with the Weinreb reagent to give amide 15.The fifteen-step process from 3 to 15 yielded this intermediate in 9.5%overall yield.

A shorter route to 10, also illustrated in FIG. 1, was also deployed.Brown crotylmetalation of TBS-protected 3-hydroxypropanal 16 (preparedquantitatively in two steps from 3), was followed by protection of theresulting alcohol 17, OsO₄-catalyzed dihydroxylation and diol cleavagewith periodate, and finally Horner-Wadsworth-Emmons homologation. Thissecond generation route improved the overall yield of 15 from 3 to 27%.

The synthesis of an exemplary “middle fragment” 29 for makingdictyostatin and analogs is shown in FIG. 2. The secondary alcohol ofknown compound 19 (see, Smith, A. B.; Beauchamp, T. J.; LaMarche, M. J.;Kaufman, M. D.; Qiu, Y. P.; Arimoto, H.; Jones, D. R.; Kobayashi, K. J.Am. Chem. Soc. 2000, 122, 8654-8664.), prepared in four steps from the(S)-Roche ester, was protected with a TBS group and the Evans auxiliarywas removed with LiBH₄ to give alcohol 21. Oxidation to the aldehyde andHorner-Emmons reaction gave the ester 22. Alkene reduction with nickelboride, saponification with LiOH and coupling with the Evans auxiliarygave amide 25. Asymmetric methylation provided one diastereomer 26 verypredominantly. Removal of the chiral auxiliary, TBS protection, and PMBdeprotection with DDQ gave the primary alcohol 28. Corey-Fuchs reactiongave the desired alkyne 29. This route from 19 to 29 proceeded in 16%overall yield.

Another route to 29, also illustrated in FIG. 2, involved conversion of21 to its iodide and asymmetric alkylation with Myers' auxiliary 30 togive amide 31. See, Myers, A.; Yang, B. Y.; Chen, H.; McKinstry, L.;Kopecky, D. J.; Gleason, J. J. Am. Chem. Soc. 1997, 119, 6496-6511.Removal of the auxiliary gave 27 in high yield, which was converted to29 by the steps described above. This second generation approach to 29doubled the overall yield from 19 to 31%. By using the enantiomer ofMyers' auxiliary 30, the epimer of 29 at C16 (dictyostatin numbering) isprepared.

The bottom and middle fragments were then coupled and the synthesis ofdictyostatin was completed as summarized in FIGS. 3 and 4. The route isflexible and generally allows access to many analogs. The Weinreb amide15 was reacted with two equivalents of the anion from alkyne 29 to givethe coupling product 32 in high yield. Reduction with the (S,S)-Noyoricatalyst gave predominantly one isomer of the alcohol 33 (see,Matsumura, K.; Hashiguchi, S.; Ikariya, T.; Noyori, R. J. Am. Chem. Soc.1997, 119, 8738-8739), whose alkyne group was reduced by Lindlarhydrogenation to alkene 34.

The newly generated secondary hydroxy group was protected with a TBSgroup to give 35. Selective deprotection of the primary TBS group withHF-pyridine in buffered pyridine at 0° C. gave 36. The aldehyde formedby Dess-Martin oxidation was reacted with the phosphonate 38 (preparedfrom 37) under Horner-Wadsworth-Emmons conditions to give the conjugatedalkene 39 in good yield. Selective reduction with nickel boride gave theketone 40, which was reduced in a purposefully unselective manner withNaBH₄ to give a 2.4:1 mixture of C19 epimers of 41, with the β isomer,necessary for preparation of (−)-dictyostatin, predominating. Theisomers of 41 were readily separated by silica gel chromatography. Aratio favoring 41β (5:1) was obtained by use of the bulkier reducingagent LiAl(O-t-Bu)₃H, whereas a 1:1 ratio of the α and β isomers wasobtained when L-Selectride was employed.

Alcohol 41β was protected with a TBS group to give 42, whose PMP acetalwas cleaved with DIBAL-H to give alcohol 43 (FIG. 4). Oxidation to thealdehyde followed by Nozaki-Hiyama addition and Peterson-typeelimination installed the (E,Z)-diene to give 44 in high yield. Theallylic trityl group was removed with ZnBr₂ to give alcohol 45.Dess-Martin oxidation to the aldehyde and Still-Gennari reaction gavethe (E,Z)-conjugated ester 46. The PMB group was removed with DDQ togive 47 and saponification with aqueous KOH in EtOH-THF to give acid 48.Yamaguchi macrolactonization gave 49 in good yield. Global deprotectionwith 3N HCl in MeOH-THF gave (−)-dictyostatin 1. The sample exhibitedspectral data identical to the natural product and the optical rotationmatched well. Thus, the previously proposed structures of dictyostatinare incorrect.

Also shown in FIG. 4 are the synthetic steps leading to tworepresentative analogs, the open-chain methyl ester 50 andC19-epi-dictyostatin 59. Ester 50 was prepared by global removal of theTBS groups from 48 in 36% yield. The C19-epi analog 59 was prepared fromalcohol 41α, as made in FIG. 3, by the same methods used for preparationof 1.

Synthesis of C16-desmethyl dictyostatin 79, another exemplary analog, isshown in FIG. 5. The synthesis proceeded from ester 23 in a mannersimilar to the existing route to 1, but with omission of the C16-methylgroup. Thus, a considerably simpler-to-make middle fragment 64 lackingthe awkward C16 stereocenter was used for construction of 79.Intermediate 23 was elongated to ester 60 by Horner-Wadsorth-Emmonsreaction. Nickel boride then DIBAL-H reduction of the ester gave alcohol61 in 76% yield. The primary hydroxy group was protected with TBSC1 togive 62 quantitatively, then the PMB group was removed to give alcohol63 in 90% yield. Oxidation of 63 to the aldehyde by using Parikh-Doeringconditions, followed by Corey-Fuchs reaction, afforded the middlefragment alkyne 64.

The remainder of the synthesis from 64 to C16-desmethyldictyostatin 79was then completed by using the same synthetic pathway described abovefor 1. Interestingly, reduction of ketone 70 (not shown, the desmethylhomologue of 40) with 3 equivalents of LiAl(O-t-Bu)₃H gave the desired71β in 95% yield, with only 5% of the α-isomer.

The synthesis of yet other representative analogs are shown in FIG. 6-8.These are epimers of dictyostatin at C6, C14 and/or C19. The alkyne 80was added to bottom fragment 81 to give alkyne 82 in 98% yield (FIG. 8).When this alkynyl ketone was subjected to Noyori reduction conditions,one major isomer 83 was formed in 87% yield. Also in this case, about 20mol % of the (S,S)-Noyori catalyst was preferred. The Noyori product 83was reduced by using Lindlar catalyst to give the cis-alkene 84 in 90%yield. When the reaction time was extended (1 day), partialover-reduction of other multiple bonds occurred.

In order to assign the configuration of the newly generated stereocenterat C9, 84 was treated with TBAF to remove both TBS groups. The resultingtriol was reacted with excess 2,2-dimethoxypropane (3.0 equiv) to formthe acetal, whose HMQC (500 MHz) NMR spectrum showed the two methylgroups of the acetonide at similar chemical shifts (24.5 ppm and 25.1ppm) and the tertiary carbon at 100.4 ppm. These data show ananti-relationship between the C7 and C9 hydroxy groups based on theRychnovsky method. The C9 hydroxy group in 84 was protected with a TBSgroup to give 85 in quantitative yield. The PMB group was then removedwith DDQ to give 86 in 84% yield. The resulting secondary hydroxy groupwas protected again by a TBS group, giving 87 in 94% yield. Selectivedeprotection of the primary TBS group was accomplished in 66% yield bytreatment with HF-pyridine complex in buffered pyridine at 0° C. for 2days to give 88 along with other deprotected byproducts. After thesuccessful coupling of the middle and bottom fragments, 88 was oxidizedto the aldehyde, which then was subjected to Horner-Emmons reaction withthe phosphonate 38, yielding 89 in 78% yield.

The alkene in α,β-unsaturated ketone 89 was reduced with nickel boridegiving 90 in 76% yield. As a side reaction, some over-reduction of theC4-C5 alkene in the bottom fragment was also observed. The C19 ketonewas reduced by NaBH₄ yielding a 1.7:1 ratio of diastereomers of 91, withthe β isomer as the major (62%), less polar product and the cc isomer asthe minor (36%), more polar product. These two diastereomers could beseparated by silica gel column chromatography. The newly generated C19hydroxy group in 91β was protected by a TBS group to give 92 in 86%yield, then the PMB acetal was cleaved with DIBAL-H to give the primaryalcohol 93 in 97% yield. Oxidation to the aldehyde and subsequentNozaki-Hiyama and Peterson syn-elimination reactions gave the diene 94in 85% yield.

Removal of the trityl group in 94 with ZnBr₂ in CH₂Cl₂-MeOH gave 95 in83% yield. This was oxidized to the aldehyde and the (E,Z)-diene wasinstalled by Still-Gennari reaction in 90% yield (FIG. 7). The PMB groupin 96 was removed by DDQ to give 97 in 90% yield, and the resultingmethyl ester was hydrolyzed with 1N aqueous KOH in EtOH-THF.Macrolactonization by the Yamaguchi method gave, surprisingly, mainlythe C2E,C4E macrolactone 99 in 78% yield. Final global TBS deprotectionyielded 100 in 25% yield.

The C19 epimer of 100 was prepared from 91α using similar reactionpathways (FIG. 8). After Yamaguchi lactonization, and global TBSdeprotection, the (E,Z)-isomer 108 (less polar, 45%) could be isolatedalong with the isomerized (E,E)-isomer 109 (more polar, 15%) in a 3:1ratio.

The methods outlined in FIGS. 1-8 are only exemplary of many possiblevariants. For example, analogs containing a C15-C16 Z-alkene can beprepared by the methods outlined in U.S. patent application Ser. No.10/655,916. Analogs lacking the C9 oxygen atom (C9-deoxy analogs) canlikewise be prepared by methods shown in that application. See, forexample, FIGS. 8 and 11, among others.

The preferred method for forming the macrolactones (often calledmacrocyclic lactones or macrolides) is the Yamaguchi lactonization. See,for example, Inanaga, J.; Kuniko, H.; Hiroko, S.; Katsuki, T.;Yamaguchi, M. Bull. Chem. Soc. Jpn. 1979, 52, 1989. An example of theYamaguchi lactonization is the conversion of hydroxy acid 48 to lactone49 in FIG. 4. Many other commons conditions suitable to effectmacrolactone formation from hydroxy acids are well known to thoseskilled in the art, and these can also be used. See, for example, Kirst,H. A. Macrolides. Large Ring Molecules; Wiley: NY; 1996; pp 345-375, andBoeckman, R. K., Jr; Goldstein, S. W. The Total Synthesis of MacrocyclicLactones. The Total Synthesis of Natural Products; Wiley: New York,1988; p 1.

The steps of semi-reduction of the C10-C11 alkyne, asymmetric reductionof the C9 ketone and (optionally) protection of the resulting alcoholcan be conducted under and assortment of different reaction conditions.For one example, see the conversion of alkynyl ketone 32 to alkynylalcohol 33, to alkenyl alcohol 34, to silyl ether 35 in FIG. 3. Thepreferred conditions for reduction of the ketone involve use of theNoyori reagent, see K. Matsumura, S. Hashiguchi, T. Ikariya, R. Noyori,J. Am. Chem. Soc. 1997, 119, 8738-39. However, many other common ketonereducing agents, both chiral and achiral, can also be used. See, forexample, Itsuno, S. Enantioselective Reduction of Ketones. Org. React.(N.Y.) 1998, 52, 395-576. In cases were two epimers of the alcohol areformed, chromatographic separation is used to isolate the individualepimers (see, for example, separation of 41 in FIG. 3). The Lindlarreduction is the preferred method of semi-reduction of the alkyne to theZ-alkene, but other methods can also be used. See for example, Siegel,S. Heterogeneous Catalytic Hydrogenation of C═C and Alkynes.Comprehensive Organic Synthesis; Pergamon Press: Oxford, 1991; pp 417,and Takaya, H. Homogeneous Catalytic Hydrogenation of C═C and Alkynes.Comprehensive Organic Synthesis; Pergamon Press: Oxford, 1991; pp 443.

The reactions in this sequence of steps can also be conducted in severalorders. The preferred order is semi-reduction of the C10-C11 alkyne,followed by asymmetric reduction of the C9 ketone followed by(optionally) protection of the resulting alcohol. Other orders ofreactions are asymmetric reduction of the ketone, protection of thealcohol and semi-reduction of the alkyne, or asymmetric reduction of theketone, semi-reduction of the alkyne and protection of the alcohol.

The preceding steps of coupling of an alkynyl anion with an activatedcarboxylic acid, see for example conversion of 15 and 29 to 32 in FIG.3, also can be conducted under different sets of conditions. A preferredmethod is the deprotonation of the alkyne with a strong base, forexample BuLi, followed by addition of a carboxylic acid derivative thatis activated with a suitable leaving group. Preferred activatedcarboxylic acids for acylation (acylating agents) are Weinreb amideswhere the leaving group is the N-methoxy-N-methyl amide group. Manyother agents such as esters, acid halides, acid imidazolides, etc. canalso be used. These have standard leaving groups such as alkoxide,imidazole and halide. The alkynyl anion can also be generated in situfrom a silylalkyne by desilylation or from a geminal-haloalkene bytreatment with two or more equivalents of a lithiating agent like BuLi.

In an alternative route, the alkynyl anion can be reacted with analdehyde instead of an activated carboxylic acid to produce a C9 alcoholdirectly after workup. This route is more direct, but mixtures ofepimers at C9 may result and chromatographic separation of the epimersmay be required. One epimer of a C9 (or other) alcohol can be convertedto the other by a Mitsunobu reaction.

Lactam analogs of dictyostatin are important as anticancer agentsbecause of their increased hydrolytic stability compared to thelactones, both in vivo and in vitro. These analogs are readily made bystarting with intermediates of the current invention, as exemplified inFIG. 9. Standard oxidation of the free C21 alcohol of 110 to a ketonefollowed by reductive amination provides 111. If desired, the C21 aminestereoisomers can be separated by chromatography. Hydrolysis of theester to the acid followed by macrolactamization provides lactam 112.The specific example of dictyostatin macrolactam 115, made for exampleby the sequence 113

14

115, is exemplary of a lactam analog of this invention.

The steps in the sequence can be conducted in different orders and alsoon different intermediates. When the C21 nitrogen atom is installedearlier in the synthesis, it is optionally protected with a standardnitrogen protecting group for the subsequent steps prior tomacrolactamization. In another approach, this nitrogen can be installedby a Mitsunobu reaction of a suitably acidic nitrogen nucleophile (forexample, azide) with a C21 alcohol. This reaction occurs with inversion,so the configuration of C23 is chosen accordingly.

For exemplary methods and conditions of reductive amination, see Baxter,E. W.; Reitz, A. B. Reductive aminations of carbonyl compounds withborohydride and borane reducing agents. Org. React. (N.Y.) 2002, 59,1-714. Methods of synthesizing macrolactams (macrocyclic lactams) arerelated to those for macrolactones. For exemplary methods andconditions, see Nubbemeyer, U. Top. Curr. Chem. 2001, 216, 125-196. Forexemplary methods and conditions for Mitsunobu reactions, see Hughes, D.L. Org. Prep. Proced. Int. 1996, 28, 127-164.

Biology

Tubulin polymerization. The abilities of the new compounds to causetubulin polymerization were determined under reaction conditionsconsisting of purified bovine brain tubulin (1 mg/mL) in the presence orabsence of microtubule-associated proteins (MAPs, 0.75 mg/mL) and GTP(100 μM). Test agents were initially screened at 10 and 40 μM. In theseexperiments, test agent-induced assembly of soluble tubulin intopolymer, with respect to the presence and absence of cofactors and atdifferent temperatures, was monitored in a multi-cuvette,temperature-controlled spectrophotometer via development of turbidity inthe solution. The initial temperature was closely controlled at 0° C.,then rapidly raised to 10° C., to 20° C., then finally to 30° C. todetermine both the temperature at which a test agent induced assembly aswell as the extent of agent-induced assembly. The temperature increaseswere followed by a rapid decrease in temperature back to 0° C. todetermine the cold-stability of polymer formed. The effects ofdictyostatin 1 and discodermolide 2 were similar and far more potentthan those of paclitaxel.

The C16-desmethyl compound 79 is especially potent among the analogs.FIG. 10 shows the simplest of its turbidity profiles in comparison tothat of dictyostatin 1 in a tubulin-only (no MAPs, no GTP, assemblysupported by monosodium glutamate) assay wherein initial temperature was0° C. for 2 min, followed by rapid rise in temperature to 30° C. for 20min, then rapid decrease to 0° C. Turbidity profiles showed that analogs50 and 59 also caused tubulin assembly at temperatures lower than 30° C.The results showed that all of the compounds had effects on the isolatedtarget, tubulin, but with a range of potencies.

Antiproliferative activity. Representative analogs were examined fortheir antiproliferative activities against human ovarian carcinoma 1A9cells and their paclitaxel-resistant mutants, 1A9/Ptx10 and 1A9/Ptx22.Each of these resistant lines contains single mutations in the majorβ-tubulin gene that confer to the cells, which do not express drugefflux pumps, appreciable tolerance to paclitaxel. Paclitaxel hadsubnanomolar potency against the parental 1A9 cells, but the mutantcells showed ca. 90- and 70-fold resistance to the drug (Table 1).Analogs 50 and 59 gave G150 values in the mid-nanomolar range. C6-epi,C14-epi-C19-epi-dictyostatin 108 and its C2E-diene derivative 109 wereantiproliferative agents, giving mid micromolar GI50 values. Even though100 also had three stereo/geometric alterations (C2E,C6-epi, C14-epi),it was a more potent antiproliferative agent than 108 and 109, showinghigh nanomolar GI50 values. With one notable exception (vide infra), thefold-resistance values for 1 and its analogs against 1A9/Ptx 10 and1A9/Ptx22 cell lines were much lower than that observed for paclitaxel.The one exception was compound 79, which appeared to be essentiallyequipotent to 1 against the parental 1A9 cells and the Ala364->Thrβ-tubulin mutant 1A9/Ptx22 cells, but experienced resistance from thePhe270->Val β-tubulin mutant 1A9/Ptx10 cells. Because these mutant cellsare not clinically relevant, the result of reduced potency is primarilyof mechanistic importance.

TABLE 1 Antiproliferative potencies of dictyostatin (1) and analogs ascompared to discodermolide (2) and paclitaxel against human ovariancarcinoma cells (1A9) and their paclitaxel-resistant, β-tubulin mutantclones (1A9/Ptx10 and 1A9/Ptx22). GI50 ± S.D., nM (fold-resistance)1A9/Ptx10 1A9/Ptx22 Compound 1A9 (Phe270 −> Val) (Ala364 −> Thr)dictyostatin- 0.69 ± 0.80 3.2 ± 2.4 (4.6) 1.3 ± 1.0 (1.9) 1 (1)discoder- 1.7 ± 1.2 6.2 ± 3.6 (3.6) 7.0 ± 8.4 (4.1) molide (2)paclitaxel 0.71 ± 0.11 64 ± 8 (90)   51 ± 9 (72)   50 56 ± 16 79 ± 13(1.4) 85 ± 2 (1.5)  59 21 ± 14 120 + 60 (5.7)  43 ± 12 (2.0) 79 0.41 ±0.52  470 ± 70 (1146) 5.6 ± 4.7 (14)  107 >500 >500 (-) >500 (-) 100310 + 40  780 + 200 (2.5) 790 + 560 (2.5) 108  28 ± 1 μM   26 ± 0 μM(0.9)   30 ± 1 μM (1.1) 109  25 ± 2 μM   25 ± 1 μM (1)   30 ± 1 μM (1.2)

Pelleting Assay (EC₅₀ determination). Dictyostatin and representativeanalogs were evaluated in a quantitative assay for their ability topromote tubulin polymerization. The EC₅₀ value (defined as test agentconcentration required to polymerize 50% of tubulin compared to control)observed for dictyostatin 1 under these conditions was 3.1±0.2 μM,similar to that obtained for discodermolide 2 (3.6±0.4 μM). Both werefar superior to paclitaxel, which gave an EC₅₀ value of 25±3 μM. TheC16-desmethyl analog 79 yielded an EC₅₀ of 14±7 μM. When the percentpolymer formed was determined in the reactions, a comparison of theactivities of all the analogs could be made. Compounds 50 and 59 showedmoderate activity. These EC₅₀ data correlated well with the relativeantiproliferative potencies of the analogs.

TABLE 2 Tubulin Assembly EC₅₀ determinations.^(a) % Tubulin polymerizedby Compound EC₅₀ (μM) ± SD (N) 50 μM test agent dictyostatin (1) 3.1 +0.2 (3) 99 + 4 discodermolide (2) 3.6 + 0.4 (3) 98 + 5 paclitaxel 25 + 3(3)  89 + 6 50 >50 (2) 39 ± 7 59 >50 (2) 30 ± 2 79 14 + 7 (3)  91 + 6100 >50 (2)  1 ± 1 108 >50 (2)  5 ± 1 109 >50 (2)  5 ± 4 ^(a)Bovinebrain tubulin (10 μM) in 0.2 M MSG, 15 min at 20° C., centrifugation andLowry determination of remaining soluble tubulin

Radiolabeled Ligand Binding Assays. The abilities of test agents toinhibit the binding of radiolabeled forms of the microtubule stabilizerspaclitaxel, discodermolide and epothilone B from tubulin polymer weredetermined. Dictyostatin 1 was equipotent to discodermolide ininhibition of the binding of radiolabeled paclitaxel and epothilone B tomicrotubules. These two compounds were the most potent of all agentstested. The open chain methyl ester 50 and the 16-desmethyl analog 79were ca. 60% as potent as 1 in inhibiting the binding of radiolabeledpaclitaxel to microtubules.

TABLE 4 Percent inhibition of radiolabel from microtubules (±SD (N,number of independent determinations)). Test Agent [³H]Pac- [³H]Disco-[¹⁴C]Epo- (4 μM) litaxel dermolide thilone B dictyostatin (1) 75 + 5 (3)40 + 3 (3)  88 + 1 (3) discodermolide (2) 76 + 6 (4) nd 90 + 1 (3)paclitaxel nd 6 + 5(3)  26 + 1 (3) 50 42 + 1 (3) nd nd 59  7 + 2 (3) ndnd 79 48 + 3 (3) nd nd 100 0 + 1   nd nd 108 0 + 1   nd nd 109 0 + 1  nd nd epothilone B nd 14 + 3    nd docetaxel 63 + 8 (4) 8 + 6 (3) 36 + 1(3) epothilone A 53 + 4 (4) 6 + 6 (3) 25 + 3 (3)

Multiparameter Fluorescence Analysis of Cellular Effects. HeLa cellswere plated on collagen-coated 384-well microtiter plates, allowed toattach, then treated for 24 h with test agents. Test agentconcentrations began at 1 μM, and two-fold dilutions were made to levelsbelow 1 nM. After the treatment period, the cells were fixed withformalin and their chromatin stained with Hoechst 33342. Cells werepermeablilized and treated with primary antibodies for α-tubulin andphosphohistone H3, and then with fluorophore-labeled secondaryantibodies. The three fluorescent channels were then examined on anArrayScan II, which gives quantitative pixel distribution and densityinformation in each channel on a per cell basis. Dictyostatin 1 was themost potent of all compounds tested, followed by paclitaxel,discodermolide and the 16-desmethyl analog 79.

TABLE 5 Minimum detectable cellular changes determined by multiparameterfluorescence high information content analysis. Nuclear PhosphohistoneTubulin polymer Compound condensation H3 intensity dictyostatin (1) 32.7± 11.7 (3) 9.6 ± 2.4 (4)  7.4 ± 2.5 (4) 50 479 ± 182 (4)  149 ± 23.6 (4) 219 ± 36 (4) 59 363 ± 146 (2) 261 ± 91 (4)   284 ± 108 (4) 79 71.5 ±18.0 (4) 34.4 ± 10.5 (4)  26.9 ± 2.9 (4) 100 >5000 (4) >5000 (4) >5000(4) 108 >5000 (4) >5000 (4) >5000 (4) 109 >5000 (4) >5000 (4) >5000 (4)discoder-   62.5 (1) 38.4 ± 21.9 (2)  64.6 ± 0.0 (2) molide (2)Paclitaxel 40.2 ± 13.9 (4) 17.5 ± 6.8 (4)   8.0 ± 2.9 (4)

EXAMPLES Chemistry

Ethyl(4R,5S,2E)-5,7-bis(tert-butyldimethylsilyloxy)-4-methylhept-2-enoate(10). A solution of triethyl phosphonoacetate (3.5 mL, 17.6 mmol) wasadded to a cooled (0° C.) stirred suspension of NaH (0.43 g, 17.0 mmol,95% dispersion in mineral oil) in THF (46 mL) dropwise over a 10 minperiod. The mixture was brought to room temperature with a water bath(30 min) and then cooled back to −78° C. and the aldehyde (2.73 g, 7.58mmol) in THF (5 mL) was added. The resulting mixture was stirred for 1 hat 0° C. then pH7 phosphate buffer solution (10 mL) and Et₂O (50 mL)were added. The mixture was allowed to warm to room temperature and thephases were separated. The organic phase was washed with sat'd NH₄Clsolution (30 mL) and brine (30 mL), dried with MgSO₄, filtered andconcentrated to give oily crude product. Purification by flashchromatography (EtOAc/hexane 1:9) afforded pure ester 10 (2.92 g, 59%for 2 steps) as a colorless oil: IR (CHCl₃) 2956, 2930, 2857, 1724,1651, 1472, 1463, 1367, 1256, 1180, 1098, 1036, 836, 775 cm⁻¹; ¹H NMR(300 MHz, CDCl₃)

6.88 (dd, J=15.8, 7.6 Hz, 1H), 5.74 (d, J=15.8 Hz, 1H), 4.19 (q, J=7.1Hz, 2H), 3.79 (ddd, J=6.7, 4.7, 4.4 Hz, 1H), 3.59 (m, 2H), 2.43 (m, 1H),1.53 (m, 3H), 1.22 (t, J=7.1 Hz, 3H), 1.01 (d, J=6.8 Hz, 3H), 0.83 (s,18H), 0.02 (m, 12H); ¹³C NMR (75 MHz, CDCl₃) δ 166.4, 150.9, 121.3,71.8, 59.9, 59.5, 42.0, 36.8, 25.82, 25.78, 26.1, 18.1, 18.0, 14.4,14.2, −4.6, −4.7, −5.4; LRMS (EI) 415 (M-CH₃), 373, 303, 147; HRMS (EI)calcd for C₂₁H₄₃O₄Si 415.2710 (M-CH₃), found 415.2712; [α]²⁰ _(D) +3.8(c 0.21, CHCl₃).

(4R,5S,2E)-5,7-bis(tert-Butyldimethylsilyloxy)-4-methylhept-2-en-1-ol(11). DIBAL-H (26.5 mL, 26.5 mmol, 1.0 M solution in hexane) was addedto the ester 10 (3.14 g. 7.30 μmol) in CH₂Cl₂ (35 mL) at −78° C.dropwise and stirred for 1 h. The reaction mixture was quenched by EtOAc(5 mL) and sat'd sodium potassium tartrate solution (20 mL) followed byvigorous stirring for 4 h. The aqueous phase was extracted with CH₂Cl₂(3×30 mL) and the combined organic layers were washed with brine (10mL). After drying over MgSO₄ and evaporation under vacuum, flash columnchromatography (hexane/EtOAc 4:1) provided 2.75 g of alcohol 11 (97%) asa colorless oil: IR(CHCl₃) 3349, 2956, 2928, 2857, 1471, 1462, 1255,1099, 836, 774 cm⁻¹; ¹H NMR (300 MHz, CDCl₃)

5.57 (m, 2H), 4.03 (m, 2H), 3.70 (ddd, J=9.7, 6.0, 3.8 Hz, 1H), 3.59 (m,2H), 2.27 (m, 1H), 2.00 (s, 1H), 1.53 (q, J=6.5 Hz, 2H), 0.96 (d, J=6.9Hz, 3H), 0.85 (s, 9H), 0.84 (s, 9H), 0.00 (m, 12H); ¹³C NMR (75 MHz,CDCl₃) δ 134.7, 129.2, 72.4, 63.6, 60.1, 41.8, 36.3, 25.9, 18.2, 18.0,15.1, 10.7, −4.6, −5.4; LRMS (EI) 370 (M-H₂O), 303, 171, 147; HRMS (EI)calcd for C₂₀H₄₂O₂Si₂ 370.2723 (M-H₂O), found 370.2725; [α]²⁰ _(D) −3.0(c 0.57, CHCl₃).

((4R,5S,2E)-5,7-bis(tert-Butyldimethylsilyloxy)-4-methylhept-2-enyloxy)triphenylmethane(12). Trityl chloride (4.1 g, 14.7 mmol) and DMAP (1.8 g, 14.7 mmol)were added to a solution of alcohol 11 (2.75 g, 7.1 mmol) in pyridine(71 mL). The mixture was heated to reflux for 18 h, cooled to ambienttemperature and added to a solution of sat'd CuSO₄ (200 mL). The mixturewas extracted with Et₂O (2×20 mL) and the combined organic extracts werewashed sat'd CuSO₄ (2×20 mL). The organic layer was separated, dried(MgSO₄), filtered, and concentrated in vacuo. Flash columnchromatography (EtOAc/hexane 1:19) provided 12 (4.46 g, quantitative) asapale yellow oil: IR (CHCl₃) 2954, 2856, 1471, 1448, 1254, 1095, 835,773, 705 cm⁻¹; ¹H NMR (300 MHz, CDCl₃)

7.56 (m, 6H), 7.32 (m, 9H), 5.79 (dd, J=15.6, 6.7 Hz, 1H), 5.65 (dd,J=15.7, 5.0 Hz, 1H), 3.85 (m, 1H), 3.74 (m, 1H), 3.66 (d, J=4.9 Hz, 1H),2.43 (m, 1H), 1.70 (q, J=6.5 Hz, 2H), 1.21 (d, J=6.9 Hz, 3H), 0.99 (s,9H), 0.97 (s, 9H), 0.154 (s, 3H), 0.150 (s, 3H), 0.13 (s, 3H), 0.12 (s,3H); ¹³C NMR (75 MHz, CDCl₃) δ 144.4, 134.2, 128.7, 127.7, 126.9, 126.8,86.8, 72.6, 65.1, 60.2, 42.1, 36.6, 26.0, 18.3, 18.1, 15.3, −4.4, −5.3;LRMS (ESI) 653.3 [M+Na]+, 422.4, 243.2; HRMS (ESI) calcd forC₃₉H₅₈O₃Si₂Na 653.3822 [M+Na]⁺, found 653.3851; [α]²⁰ _(D) −1.9 (c 0.42,CHCl₃).

(3S,4R,5E)-3-(tert-Butyldimethylsilyloxy)-4-methyl-7-(trityloxy)hept-5-en-1-ol(13). HF-pyridine in pyridine (40 mL, prepared by slow addition of 12 mLpyridine to 3 mL HF-pyridine complex followed by dilution with 25 mLTHF) was added to a solution of TBS ether 12 (4.46 g, 7.07 mmol) in THF(10 mL). The mixture was stirred overnight at room temperature andquenched with sat'd NaHCO₃ (100 mL). The aqueous layer was separated andextracted with Et₂O (3×50 mL). The combined organic layers were washedwith sat'd CuSO₄ (3×50 mL), dried over MgSO₄, and concentrated. Flashcolumn chromatography (EtOAc/hexane 1:4) afforded 3.26 g (89%) ofalcohol 13 as a colorless oil: IR(CHCl₃) 3407, 2955, 2928, 2856, 1490,1471, 1448, 1254, 1058, 1031, 836, 773, 705 cm⁻¹; ¹H NMR (300 MHz,CDCl₃)

7.57 (m, 6H), 7.37 (m, 9H), 5.78 (dd, J=15.6, 6.5 Hz, 1H), 5.73 (dt,J=15.5, 4.8 Hz, 1H), 3.91 (m, 1H), 3.82 (d, J=5.9 Hz, 2H), 3.69 (d,J=4.4 Hz, 2H), 2.51 (m, 1H), 2.22 (br, 1H), 1.77 (m, 2H), 1.13 (d, J=6.8Hz, 3H), 1.03 (s, 9H), 0.21 (s, 3H), 0.19 (s, 3H); ¹³C NMR (75 MHz,CDCl₃) δ 144.2, 134.1, 128.6, 127.7, 127.1, 126.9, 86.8, 74.3, 64.9,60.4, 42.0, 34.8, 25.9, 18.0, 14.5, −4.4, −4.6; LRMS (ESI) 539.2[M+Na]+, 243.2; HRMS (ESI) calcd for C₃₃H₄₄O₃Si₁Na 539.2957 [M+Na]⁺,found 539.2976; [D]²⁰ _(D) −2.8 (c 2.0, CHCl₃).

(3S,4R,5E)-3-(tert-Butyldimethylsilyloxy)-N-methoxy-N,4-dimethyl-7-(trityloxy)hept-5-enamide(15). Sulfur trioxide pyridine complex (3.02 g, 19.1 mmol) was added toa stirred solution of alcohol 13 (3.26 g, 6.31 mmol) and triethylamine(2.6 mL, 19.1 mmol) in anhydrous CH₂Cl₂ (6 mL) and DMSO (12 mL) at 0° C.The reaction mixture was stirred at the ambient temperature for 1 h. Themixture was diluted with Et₂O (100 mL) and washed with aqueous 0.5 N HCl(50 mL) and brine (10 mL). The separated organic layer was dried overMgSO₄. Filtration and concentration followed by short flash columnchromatography (hexane/EtOAc 4:1) provided the crude aldehyde as acolorless oil, which was used without further purification. A solutionof the aldehyde in THF (25 mL) and H₂O (12 mL) was treated with2-methyl-2-butene in THF (2M, 18 mL, 9.0 mmol), NaH₂PO₄.H₂O (2.6 g, 18.8mmol) and NaClO₂ (2.1 g, 18.6 mmol). The reaction mixture was stirredfor 2 h, diluted with 1N HCl (20 mL) and extracted with CH₂Cl₂ (2×40mL). The combined organic layers were dried over MgSO₄, concentrated invacuo and the crude acid was used for the next reaction without furtherpurification. N,O-Dimethylhydroxylamine hydrochloride (0.62 g, 6.36mmol), Et₃N (0.88 mL, 6.31 mmol), DMAP (0.63 mmol) were successivelyadded to a solution of the crude acid in CH₂Cl₂ (10 mL). The reactionmixture was cooled to 0° C., and DCC (1.30 g, 6.30 mmol) was added. Themixture was stirred at ambient temperature for 15 h and filtered. Thefiltrate was washed with 0.5 N HCl, saturated aqueous NaHCO₃, and brine,dried over anhydrous MgSO₄ and concentrated. Purification by columnchromatography over silica gel (hexane/EtOAc 4:1) gave the Weinreb amide15 (2.65 g, 73% for 3 steps) as a colorless oil: IR (CHCl₃) 2956, 2929,2855, 1663, 1448, 1252, 1083, 1032, 836 cm⁻¹; ¹H NMR (300 MHz, CDCl₃)

7.58 m, 6H), 7.37 (m, 9H), 5.89 (dd, J=15.6, 7.6 Hz, 1H), 5.72 (dt,J=15.6, 5.2 Hz, 1H), 4.38 (ddd, J=8.0, 5.0, 3.0 Hz, 1H), 3.74 (s, 3H),3.70 (d, J=5.1 Hz, 2H), 3.27 (s, 3H), 2.79 (dd, J=15.1, 7.4 Hz, 1H),2.52 (m, 2H), 1.20 (d, J=6.9 Hz, 3H), 1.02 (s, 9H), 0.22 (s, 3H), 0.16(s, 3H); ¹³C NMR (75 MHz, CDCl₃) δ 172.6, 144.2, 133.3, 128.5, 127.7,127.5, 126.8, 86.7, 72.4, 64.8, 61.2, 42.4, 36.3, 31.9, 25.8, 18.0,15.7, −4.6, −5.0; LRMS (ESI) 596.2 [M+Na]⁺, 449.2, 243.0; HRMS (ESI)calcd for C₃₅H₄₇O₄NSiNa 596.3172 [M+Na]⁺, found 596.3165; [α]²⁰ _(D)−14.7 (c 0.65, CHCl₃).

(R)-3-((2R,3S,4S)-5-(4-Methoxybenzyloxy)-3-(tert-butyldimethylsilyloxy)-2,4-dimethylpentanoyl)-4-benzyloxazolidin-2-one(20). 2,6-Lutidine (5.14 mL, 44.2 mmol) and TBSOTf (9.36 mL, 40.8 mmol)were added to a solution of 19 (15.0 g, 33.9 mmol) in CH₂Cl₂ (340 mL)stirred at 0° C. The mixture was stirred at 0° C. for 2 h and thenquenched by the addition of saturated aqueous NaHCO₃. The phases wereseparated and the aqueous layer was extracted with CH₂Cl₂. The combinedorganic phases were washed with 0.5 M aqueous NaHSO₄. The organic phasewas dried over Na₂SO₄, filtered and concentrated under reduced pressure.The residue was purified by flash chromatography (hexane/EtOAc 4:1) togive 20 (17.9 g, 95%) as a colorless oil: IR (film) 1781, 1696, 1513,1383, 1248, 1209, 1110, 1042 cm⁻¹; ¹H NMR (300 MHz, CDCl₃)

7.35-7.28 (m, 7H), 6.85 (d, J=8,7 Hz, 1H), 4.49 (m, 1H), 4.38 (d, J=11.7Hz, 1H), 4.34 (d, J=11.7 Hz), 4.03 (m, 3H), 3.81 (m, 3H), 3.77 (s, 3H),3.54 (dd, J=9.2, 5.6 Hz, 1H), 3.22 (dd, J=13.3, 3.1 Hz, 1H), 3.17 (dd,J=9.1, 5.9 Hz, 1H), 2.72 (dd, J=13.3, 9.6 Hz, 1H), 1.97 (m, 1H), 1.25(d, J=6.5 Hz, 3H), 1.02 (d, J=7.0 Hz, 3H), 0.91 (s, 9H), 0.07 (s, 6H);¹³C NMR (75 MHz, CDCl₃) δ 176.4, 159.4, 153.1, 135.8, 131.1, 129.8,129.3, 129.2, 127.6, 75.6, 72.9, 72.0, 66.1, 55.8, 55.6, 41.9, 39.3,38.0, 26.4, 18.7, 15.3, 15.2, −3.5, −3.6; HRMS (ESI) calcd forC₃₁H₄₅NO₆SiNa578.2914 [M+Na]⁺, found 578.2923; [α]²⁰ _(D) −8.1 (c 7.6,CHCl₃).

(2S,3R,4S)-5-(4-Methoxybenzyloxy)-3-(tert-butyldimethylsilyloxy)-2,4-dimethylpentan-1-ol(21). Dry MeOH (1.05 mL, 26.0 mmol) then LiBH₄ (13 mL, 2.0 M solution inTHF, 26 mmol) were added to a stirred solution of 20 (4.79 g, 8.62 mmol)in THF (75 mL) at 0° C. The resulting mixture was stirred at 0° C. for45 min and at room temperature for 1 h. The solution was cooled to 0° C.and treated carefully with a 1.0 M aqueous NaOH (50 mL). The phases wereseparated and the aqueous phase was extracted with CH₂Cl₂. The combinedorganic phases were washed with brine, dried over MgSO₄, filtered andconcentrated under reduced pressure. The residue was purified by flashchromatography (hexane/EtOAc 7:3) to give the alcohol 21 (2.98 g, 90%)as a colorless oil: IR (film) 3425, 1613, 1513, 1463, 1249, 1091, 1037cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ 7.26 (d, J=8.5 Hz, 2H), 6.88 (d, J=8.5Hz, 2H), 4.47 (d, J=11.7 Hz, 1H), 4.40 (d, J=11.7 Hz, 1H), 3.84 (s, 3H),3.75 (dd, J=5.7, 2.9 Hz, 1H), 3.52 (m, 3H), 3.28 (dd, J=9.1, 7.1 Hz,1H), 2.10 (br, 1H), 2.05 (m, 1H), 1.93-1.81 (m, 1H), 0.97 (d, J=7.0 Hz,3H), 0.90 (s, 9H), 0.87 (d, J=7.1 Hz, 3H), 0.07 (s, 3H), 0.05 (s, 3H);¹³C NMR (75 MHz, CDCl₃) δ 159.2, 130.7, 129.3, 113.8, 74.8, 72.8, 72.7,66.3, 55.4, 39.0, 37.7, 26.2, 18.4, 15.2, 12.0, −4.1; HRMS (ESI) calcdfor C₁₈H₃₁O₃SiNa 323.2042 [M+Na]⁺, found 323.2035; [α]²⁰ _(D) −0.76 (c2.9, CHCl₃).

(4S,5R,6S,2E)-Ethyl-7-(4-methoxybenzyloxy)-5-(tert-butyldimethylsilyloxy)-4,6-dimethylhept-2-enoate(22). The procedure for 10 was used with the aldehyde from 21 (17.5 g,31.6 mmol), Py.SO₃ (15.2 g, 95.5 mmol) and Et₃N (13.3 mL, 95.5 mmol),NaH (0.90 g, 39.7 mmol) and triethylphosphonoacetate (7.2 mL, 40.3 mmol)to yield 8.96 g (63% for 3 steps) of the ester 22 by flash columnchromatography (EtOAc/Hexane 1:9) as a colorless oil: IR (CHCl₃) 2957,2931, 2856, 1720, 1651, 1613, 1513, 1463, 1366, 1250, 1180, 1093, 1077,837 cm⁻¹; ¹H NMR (300 MHz, CDCl₃)

7.31-7.27 (m, 2H), 7.03 (dd, J=15.8, 7.8 Hz, 1H), 6.93-6.91 (m, 2H),5.83 (dd, J=15.8, 1.3 Hz, 1H), 4.48-4.40 (m, 2H), 4.23 (q, J=7.1 Hz,2H), 3.84 (s, 3H), 3.67 (m, 1H), 3.52 (m, 1H), 3.30 (dd, J=9.1, 7.2 Hz,1H), 2.59 (m, 1H), 2.00 (m, 1H), 1.33 (t, J=7.1 Hz, 3H), 1.09 (d, J=6.8Hz, 3H), 1.01 (d, J=7.0 Hz, 3H), 0.94 (s, 9H), 0.08 (m, 6H); ¹³C NMR (75MHz, CDCl₃) δ 166.5, 159.0, 152.7, 130.6, 129.0, 120.4, 113.6, 76.8,72.5, 71.8, 60.0, 55.1, 40.2, 38.0, 26.0, 18.2, 14.8, 14.3, 14.2, −4.0,−4.2; LRMS (ESI) 473.2 [M+Na]+; HRMS (ESI) calcd forC₂₅H₄₂O₅SiNa473.2699 [M+Na]⁺, found 473.2716; [α]²⁰ _(D) −28.3 (c 0.41,CHCl₃).

(4S,5R,6S)-Ethyl-7-(4-methoxy)benzyloxy)-5-(tert-butyldimethylsilyloxy)-4,6-dimethylheptanoate(23). NiCl₂.6H₂O (2.4 g, 10.1 mmol) then portionwise NaBH₄ (1.50 g, 39.7mmol) were added to a stirred solution of unsaturated ketone 22 (8.96 g,19.9 μmol) in MeOH (66 mL), THF (20 mL) at 0° C. After 1 h, the solventwas evaporated and filtered with Celite using Et₂O as an eluent (60 mL).The organic phase was concentrated and the residue was purified by flashchromatography (EtOAc/hexane 1:9) to yield 8.76 g of 23 (97%) as acolorless oil: IR (CHCl₃) 2957, 2856, 1737, 1613, 1513, 1463, 1374,1249, 1172, 1091, 1038, 836, 773 cm⁻¹; ¹H NMR (300 MHz, CDCl₃)

7.40-7.37 (m, 2H), 7.02-6.99 (m, 2H), 4.59-4.50 (m, 2H), 4.25 (q, J=7.1Hz, 2H), 3.91 (s, 3H), 3.66-3.62 (m, 2H), 3.40 (dd, J=8.8, 7.3 Hz, 1H),2.52-2.33 (m, 2H), 2.13-2.02 (m, 1H), 1.90-1.82 (m, 1H), 1.78-1.57 (m,2H), 1.38 (t, J=7.1 Hz, 3H), 1.09 (d, J=6.9 Hz, 3H), 1.03 (s, 9H), 1.00(d, J=6.5 Hz, 3H), 0.19 (s, 3H), 0.18 (s, 3H); ¹³C NMR (75 MHz, CDCl₃) δ173.6, 158.9, 130.7, 129.0, 113.5, 76.8, 72.5, 60.0, 55.0, 38.0, 35.6,32.5, 29.9, 26.0, 18.3, 14.9, 14.1, 13.7, −3.9, −4.2; LRMS (ESI) 475.3[M+Na]⁺; HRMS (ESI) calcd for C₂₅H₄₄O₅SiNa475.2856 [M+Na]⁺, found473.2877; [α]²⁰ _(D) −6.0 (c 1.9, CHCl₃).

(4S,5R,6S)-7-(4-Methoxybenzyloxy)-5-(tert-butyldimethylsilyloxy)-4,6-dimethylheptanoicacid (24). Aqueous LiOH (1N, 193 mL, 0.19 mol) was added to a THF—H₂Osolution of 23 (8.76 g, 19.4 mmol). The resulting solution was warmed to60 oC and stirred with heating for 6 h. Aqueous 1N HCl was added to givea neutral pH and the mixture was extracted with CH₂Cl₂, dried overMgSO4, filtered and evaporated to yield 8.22 g of crude acid 24, whichwas used without further purification: ¹H NMR (300 MHz, CDCl₃) δ7.24-7.22 (m, 2H), 6.86-6.83 (m, 2H), 4.39 (m, 2H), 3.77 (s, 3H), 3.69(q, J=7.0 Hz, 1H), 3.52 (m, 1H), 3.47 (q, J=7.0 Hz, 1H), 3.19 (t, J=8.5Hz, 1H), 2.16 (m, 1H), 1.90 (m, 1H), 1.65-1.51 (m, 2H), 1.21 (t, J=7.0Hz, 2H), 0.92-0.85 (m, 12H), 0.81 (d, J=6.3 Hz, 3H), 0.00 (m, 6H); ¹³CNMR (75 MHz, CDCl₃) δ 181.0, 158.9, 130.6, 129.1, 113.6, 72.5, 65.8,58.0, 55.1, 37.8, 30.6, 26.1, 18.3, 18.1, 15.2, 14.0, −3.5, −4.1.

(R)-3-((4S,5R,6S)-7-(4-Methoxybenzyloxy)-5-(tert-butyldimethylsilyloxy)-4,6-dimethylheptanoyl)-4-benzyloxazolidin-2-one(25). A solution of the acid 24 (8.22 g, 19.4 mmol) and Et₃N (5.40 mL,38.8 mmol) in 100 mL of dry THF was cooled to −78° C. and treateddropwise with pivaloyl chloride (2.86 g, 23.3 mmol), stirred in the coldfor 2 h and warmed to 0° C. prior to the addition of the oxazolidinone(3.5 g, 19.8 mmol) and LiCl (2.46 g, 58.8 mmol). This mixture wasstirred overnight at room temperature and diluted with water (200 mL).The separated aqueous phase was extracted with ether (100 mL) and thecombined organic layers were dried and evaporated to give a residue thatwas chromatographed to yield 7.91 g (70% for 2 steps) of imide 25 byflash colurn chromatography (EtOAc/hexane 1:4) as a colorless oil: ¹HNMR (300 MHz, CDCl₃) δ 7.41-7.23 (m, 7H), 6.94-6.91 (m, 2H), 4.71 (m,1H), 4.51 (d, J=11.6 Hz, 1H), 4.46 (d, J=11.6 Hz, 1H), 4.25-4.16 (m,2H), 3.84 (s, 3H), 3.63-3.58 (m, 2H), 3.37-3.31 (m, 2H), 3.14-3.04 (m,1H), 2.94-2.86 (m, 1H), 2.79 (dd, J=13.3, 9.7 Hz, 1H), 2.04 (m, 1H),1.87-1.60 (m, 3H), 1.03 (d, J=6.9 Hz, 3H), 0.99-0.97 (m, 12H), 0.14 (s,3H), 0.12 (s, 3H); ¹³C NMR (75 MHz, CDCl₃) δ 173.1, 158.8, 153.3, 135.2,130.7, 129.3, 129.0, 128.8, 127.1, 113.5, 77.1, 72.5, 72.4, 65.9, 55.1,54.9, 37.9, 37.7, 35.6, 33.7, 29.2, 26.0, 18.3, 14.9, 13.9, −3.8, −4.2.

(R)-3-((2R,4S,5R,6S)-7-(4-Methoxybenzyloxy)-5-(tert-butyldimethylsilyloxy)-2,4,6-trimethylheptanoyl)-4-benzyloxazolidin-2-one(26). NaHMDS (1 M in THF, 14.9 mL, 14.9 mmol) was added dropwise over a30 min period to a cooled (−78° C.) suspension of the imide 25 (7.91 g,13.6 mmol) in THF (45 mL). After 15 min of stirring, the resulting coldsolution was treated with MeI (2.53 mL, 40.8 mmol) and allowed to stirat −78° C. for 3 h before being warmed to 25° C. overnight (12 h) Thereaction was quenched with H₂O (100 mL), and the aqueous layer wasextracted with Et₂O (3×150 mL). The combined organic extracts were dried(MgSO₄), concentrated in vacuo and chromatographed (EtOAc/hexane 1:9) toprovide 5.97 g (74%) of 26 as a colorless oil: ¹H NMR (300 MHz, CDCl₃) δ7.42-7.26 (m, 7H), 6.95-6.92 (m, 2H), 4.71 (m, 1H), 4.51 (m, 2H), 4.18(m, 2H), 3.95 (m, 1H), 3.84 (s, 3H), 3.63 (dd, J=8.9, 3.8 Hz, 1H), 3.57(dd, J=6.4, 2.7 Hz, 1H), 3.35 (t, J=8.5 Hz, 1H), 3.28 (dd, J=13.3, 3.1Hz, 1H), 2.83 (dd, J=13.3, 9.4 Hz, 1H), 2.10-1.95 (m, 2H), 1.68 (m, 1H),1.38 (ddd, J=14.1, 9.8, 4.9 Hz, 1H), 1.31 (d, J=6.8 Hz, 3H), 1.04 (d,J=6.9 Hz, 3H), 0.98 (s, 9H), 0.95 (d, J=6.7 Hz, 3H), 0.14 (s, 3H), 0.13(s, 3H); ¹³C NMR (75 MHz, CDCl₃) δ 176.8, 158.8, 152.8, 135.1, 130.8,129.3, 128.9, 128.7, 127.1, 113.5, 77.6, 72.6, 72.4, 65.7, 55.0, 38.9,38.0, 37.6, 35.3, 33.8, 26.0, 18.8, 18.3, 14.9, 13.8, −3.8, −4.2.

(2R,4S,5R,6S)-7-(4-Methoxybenzyloxy)-5-(tert-butyldimethylsilyloxy)-2,4,6-trimethylheptan-1-ol(27). n-BuLi (2.5 M in hexane, 17.6 mL, 44 mmol) was added to a solutionof diisopropylamine (6.65 mL, 47.4 mmol) in THF (48 mL) stirred at −78°C. The solution was stirred at −78° C. for 5 min and warmed to 0° C. for15 min. Borane-ammonia complex (90%, 1.55 g, 45.2 mmol) was added andthe resulting mixture was stirred at 0° C. for 15 min, warmed to roomtemperature for 15 min and then cooled to 0° C. A solution of amide 26(6.62 g, 11.3 mmol) in THF (35 mL) was added dropwise and the reactionwas stirred at 0° C. for 1 h and then at room temperature for 2 h. Themixture was cooled to 0° C. and quenched carefully with saturatedaqueous NH₄Cl. The mixture was extracted with Et₂O and the combinedorganic extracts were washed with brine, dried over MgSO₄, filtered andconcentrated under reduced pressure. The residue was purified by flashchromatography (step gradient of 4:1 to 7:3 hexane/EtOAc) to afford thealcohol 27 (4.57 g, 96%) as a colorless oil: IR (film) 3410, 1612, 1513,1249, 1067, 1038 cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ 7.26 (d, J=8.6 Hz, 2H),6.88 (d, J=8.6 Hz, 2H), 4.44 (d, J=11.7 Hz, 1H), 4.39 (d, J=11.7 Hz,1H), 3.81 (s, 3H), 3.51 (m, 2H), 3.44 (dd, J=5.6, 3.4 Hz, 1H), 3.37 (dd,J=10.6, 6.5 Hz, 1H), 3.22 (dd, J=9.0, 7.0 Hz, 1H), 2.03-1.95 (m, 1H),1.78-1.62 (m, 2H), 1.53 (br, 1H), 1.41 (ddd, J=13.5, 7.5, 5.8 Hz, 1H),0.95 (d, J=6.9 Hz, 3H), 0.94 (d, J=6.7 Hz, 3H), 0.88 (s, 9H), 0.87 (d,J=6.9 Hz, 3H), 0.04 (s, 3H), 0.03 (s, 3H); ¹³C NMR (75 MHz, CDCl₃) δ159.2, 130.9, 129.4, 113.9, 77.5, 72.8, 67.7, 55.4, 38.3, 38.0, 33.6,33.2, 26.3, 18.6, 18.0, 15.6, 15.5, −3.5, −3.8; [α]²⁰ _(D) −6.3 (c 1.7,CHCl₃).

(2S,3R,4S,6R)-3,7-bis(tert-Butyldimethylsilyloxy)-2,4,6-trimethylheptan-1-ol(28). TBSCl (4.16 g, 27.6 mmol) was added to a solution of alcohol 27(5.86 g, 13.8 mmol), imidazole (2.89 g, 41.4 mmol), and DMAP (169 mg,1.38 mmol) in CH₂Cl₂ (55 mL). The resulting white suspension was stirredat room temperature for 2 h and the volatiles were removed under reducedpressure. The residue was dissolved in hexane and brine. The phases wereseparated and the organic layer was washed with brine, dried over MgSO₄,filtered and concentrated under reduced pressure. The residue waspurified by flash chromatography (hexane/EtOAc 19:1) to afford the TBSprotected alcohol (7.04 g, 95%) as a colorless oil: IR (film) 1513,1471, 1463, 1249, 1091, 1039 cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ 7.30 (d,J=8.6 Hz, 2H), 6.91 (d, J=8.6 Hz, 2H), 4.48 (d, J=11.9 Hz, 1H), 4.44 (d,J=11.9 Hz, 1H), 3.82 (s, 3H), 3.60-3.49 (m, 3H), 3.39-3.28 (m, 3H),2.05-1.95 (m, 1H), 1.80-1.66 (m, 2H), 1.49-1.40 (m, 2H), 1.02 (d, J=6.9Hz, 3H), 1.0-0.91 (m, 24H), 0.10 (s, 3H), 0.09 (s, 3H), 0.08 (s, 3H);¹³C NMR (75 MHz, CDCl₃) δ 159.2, 131.1, 129.3, 127.9, 77.3, 73.1, 72.8,68.4, 55.3, 38.9, 38.5, 33.5, 26.4, 26.2, 18.7, 18.6, 18.1, 15.3, 15.1,−3.4, −3.8, −5.2; [α]²⁰ _(D) −15.9 (c 0.47, CHCl₃). A solution of aboveTBS protected alcohol (5.28 g, 9.8 mmol) in CH₂Cl₂ (332 mL) and pH 7phosphate buffer solution (33 mL) was treated with DDQ (3.34 g, 14.7mmol). The reaction was stirred at room temperature for 1 h and wasquenched with saturated aqueous NaHCO₃ solution. The phases wereseparated and the aqueous layer was extracted with CH₂Cl₂. The combinedorganic extracts were washed with water, dried over MgSO₄, filtered, andconcentrated under reduced pressure. The residue was purified by flashchromatography (hexane/EtOAc 97:3 to 93:7) to afford 28 (4.01 g, 98%) asa colorless oil: IR (film) 3353, 1472, 1463, 1388, 1360, 1255, 1091,1030, 1005 cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ 3.60 (d, J=5.3 Hz, 2H),3.55-3.45 (m, 2H), 3.32 (dd, J=9.7, 6.7 Hz, 1H), 2.49 (br, 1H), 1.45(ddd, J=13.5, 7.5, 5.3 Hz, 1H), 0.95 (d, J=7.1 Hz, 3H), 0.92 (s, 9H),0.89 (s, 9H), 0.93-0.87 (m, 6H), 0.11 (s, 3H), 0.09 (s, 3H), 0.04 (s,6H); ¹³C NMR (75 MHz, CDCl₃) δ 80.9, 68.0, 66.2, 38.4, 37.8, 35.4, 33.5,26.3, 26.1, 18.5, 18.3, 16.2, 15.7, −3.6, −3.9, −5.3; [α]²⁰ _(D) −16.1(c 4.4, CHCl₃).

(3S,4R,5S,7R)-4-(tert-Butyldimethylsilyloxy)-7-((tert-butyldimethylsilyloxy)methyl)-3,5-dimethyloct-1-yne(29). Sulfur trioxide pyridine complex (5.44 g, 34.2 mmol) was added toa solution of 28 (4.78 g, 11.4 mmol) and triethylamine (4.77 mL, 34.2mmol) in CH₂Cl₂ (23 mL) and DMSO (46 mL) at 0° C. The mixture wasstirred at 0° C. for 1 h and then diluted with Et₂O. The organic phasewas washed with cold 0.5 M aqueous NaHSO₄ and then with brine. Theorganic layer was dried over MgSO₄, filtered and concentrated underreduced pressure. The residue was purified by short flash chromatography(hexane/EtOAc 9:1) to afford the crude aldehyde as a golden oil whichwas used directly in the next reaction without further purification.Carbon tetrabromide (7.56 g, 22.8 mmol) was added to a solution oftriphenylphosphine (12.3 g, 45.6 mmol) in CH₂Cl₂ (56 mL) at 0° C. Theresulting dark-red mixture was stirred at 0° C. for 10 min. A solutionof the crude aldehyde and 2,6-lutidine (2.66 mL, 22.8 mmol) in CH₂Cl₂(45 mL) was added dropwise. The dark-brown mixture was stirred at 0° C.for 1 h and then quenched with a saturated aqueous NH₄Cl. The layerswere separated and the aqueous phase was extracted with CH₂Cl₂. Thecombined organic extracts were washed with H₂O, dried over MgSO₄,filtered and concentrated under reduced pressure. The residue waspurified by short flash chromatography (hexane 100%) to afford thedibromoolefin (4.76 g, 73% yield from the alcohol) as a colorless oilthat was used without further purification. A solution of thedibromoolefin (4.76 g, 8.2 mmol) in THF (40 mL) stirred at −78° C. wastreated with n-BuLi (1.6 M in hexane, 15.4 mL, 24.6 mmol). The solutionwas stirred at −78° C. for 2 h and then quenched with saturated aqueousNH₄Cl. The mixture was allowed to reach room temperature and was dilutedwith Et₂O. The aqueous layer was extracted with Et₂O. The combinedorganic extracts were washed with brine, dried over MgSO₄, filtered andconcentrated under reduced pressure. The residue was purified by flashchromatography (hexane:EtOAc 97:3) to afford the pure alkyne 29 (3.26 g,95%) as a colorless oil: IR (film) 3313, 2100, 1472, 1463, 1252, 1088,1005 cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ 3.53-3.48 (m, 2H), 3.33 (d, J=9.7,6.8 Hz, 1H), 2.62 (ddddd, J=7.2, 7.2, 7.2, 5.1, 2.5 Hz, 1H) 2.03 (d,J=2.5 Hz, 1H), 1.97-1.80 (m, 1H), 1.73-1.6 (m, 1H), 1.47 (m, 1H), 1.21(d, J=7.1 Hz, 3H), 0.99-0.91 (m, 6H), 0.95 (s, 9H), 0.93 (s, 9H), 0.13(s, 3H), 0.11 (s, 3H), 0.08 (s, 6H); ¹³C NMR (75 MHz, CDCl₃) δ 87.9,77.8, 70.2, 68.5, 39.2, 33.9, 33.7, 32.3, 26.4, 26.3, 18.6, 17.9, 17.5,15.7, −3.6, −5.1; HRMS (ESI) calcd for C₂₂H₄₅O₂Si₂Na397.2958 [M+Na]⁺,found 397.2950; [α]²⁰ _(D) −8.2 (c 3.1, CHCl₃).

(2R,4S,5R,6S)-7-(4-Methoxybenzyloxy)-5-(tert-butyldimethylsilyloxy)-N-((1S,2S)-1-hydroxy-1-phenylpropan-2-yl)-N,2,4,6-tetramethylheptanamide(31). PPh₃ (7.05 g, 26.2 mmol), imidazole (1.78 g, 26.2 mmol),diisopropylethylamine (4.6 mL, 26.2 mmol) in benzene (80 mL), diethylether (165 mL) and acetonitrile (33 mL) were stirred at room temperatureand treated with iodine (6.65 g, 26.2 mmol). The resulting mixture wasvigorously stirred until the formation of a beige suspension. A solutionof the alcohol 21 (5.0 g, 13.1 mmol) in Et₂O (20 mL) was added dropwiseto the suspension and the resulting mixture was stirred at roomtemperature for 30 min. The reaction was quenched with saturated aqueousNaHCO₃ and diluted with Et₂O. The aqueous phase was extracted with Et₂Oand the combined organic extracts were washed with brine, dried overMgSO₄, filtered and concentrated under reduced pressure. The residue wastriturated with hexane and the triturate was concentrated under reducedpressure. This procedure was repeated two more times to afford theiodide as a colorless oil that was used directly in the next reaction. Asolution of n-BuLi in hexane (2.5 M, 21 mL, 52.4 mmol) was added to asuspension of LiCl (7.05 g, 166.4 mmol) and diisopropylamine (7.85 mL,56.3 mmol) in THF (40 mL) at −78° C. The suspension was stirred at −78°C. for 5 min, 0° C. for 15 min and then cooled to −78° C. A solution of(S,S)-pseudoephedrine propionamide (Meyer's auxiliary, 30) (6.09 g, 27.5mmol) in THF (70 mL) was added dropwise. The resulting mixture wasstirred at −78° C. for 1 h, at 0° C. for 15 min and at room temperaturefor 5 min. The suspension was cooled to 0° C. and the iodide was addedas a solution in THF (6 mL followed by a 6 mL rinse). The reactionmixture was stirred at room temperature for 24 h and quenched withhalf-saturated aqueous NH₄Cl. The aqueous layer was extracted with EtOAcand the combined organic extracts were dried over Na₂SO₄, filtered andconcentrated under reduced pressure to give a residue which was purifiedby flash chromatography (hexane/EtOAc 1:1) to afford the amide 31 (6.69g, 87%) as a colorless oil: IR (film) 3387, 1616, 1513, 1463, 1248,1087, 1037 cm⁻¹; HRMS (ESI) calcd for C₃₄H₅₆NO₅Si 586.3928, found586.3940; [α]²⁰ _(D) +23.2 (c 1.26, CHCl₃).

(4R,5S,10S,11R,12S,14R,2E)-5,11,15-tris(tert-Butyldimethylsilyloxy)-4,10,12,14-tetramethyl-1-(trityloxy)pentadec-2-en-8-yn-7-one(32). Alkyne 29 (4.12 g, 10.0 mmol) was dissolved in THF (100 mL) andcooled to −78° C. n-BuLi (6.25 mL, 1.6 M hexane solution) was addedslowly. After 5 min, the mixture was warmed to 0° C. and stirred for 30min. The mixture was then cooled to −78° C. and amide 15 (6.47 g, 11.3mmol) in THF (5 mL) was added slowly. After 5 min, the solution waswarmed to 0° C. and stirred for 30 min. The reaction was quenched withsaturated aqueous NH₄Cl and the mixture was partitioned in a separatoryfunnel. The aqueous phase was extracted with Et₂O (3×20 mL). Thecombined organic extracts were washed with brine and dried over MgSO₄.Filtration and concentration under reduced pressure, followed by flashchromatography on silica gel (hexane/EtOAc 19:1), afforded the ynone 32(9.70 g, 93%) as a pale yellow oil: IR (CHCl₃) 2955, 2928, 2856, 2209,1676, 1471, 1462, 1252, 1085, 836, 774 cm⁻¹; ¹H NMR (300 MHz, CDCl₃)

7.56 m, 6H), 7.36 (m, 9H), 5.80 (dd, J=15.6, 7.1 Hz, 1H), 5.69 (dt,J=15.7, 4.8 Hz, 1H), 4.37 (m, 1H), 3.69 (d, J=4.7 Hz, 2H), 3.61 (m, 1H),3.58 (dd, J=9.7, 5.0 Hz, 1H), 3.43 (dd, J=9.7, 6.5 Hz, 1H), 2.87 (m,1H), 2.73 (m, 1H), 2.46 (m, 1H), 1.88 (m, 1H), 1.76 (m, 1H), 1.59 (m,1H), 1.31 (d, J=7.1 Hz, 3H), 1.15 (d, J=6.8 Hz, 3H), 1.05 (m, 1H), 1.00(m, 34H), 0.194 (s, 3H), 0.190 (s, 3H), 0.17 (s, 3H), 0.15 (s, 3H), 0.14(s, 6H); ¹³C NMR (75 MHz, CDCl₃) δ 186.1, 144.2, 132.9, 128.6, 127.7,126.9, 96.8, 86.8, 83.1, 71.5, 68.0, 64.9, 50.0, 42.3, 38.1, 34.4, 33.2,32.1, 26.01, 25.96, 25.85, 18.3, 18.0, 17.9, 17.2, 15.5, 15.4, −3.8,−4.1, −4.6, −4.7, −5.4; LRMS (ESI) 947.5 [M+Na]+, 562.3, 243.1; HRMS(ESI) calcd for C₅₆H₈₈O₅Si₃Na 947.5837 [M+Na]⁺, found 947.5875; [α]²⁰_(D) −12.0 (c 0.54, CHCl₃).

(4R,5S,7S,10S,11R,12S,14R,2E)-5,11,15-tris(tert-Butyldimethylsilyloxy)-4,10,12,14-tetramethyl-1-(trityloxy)pentadec-2-en-8-yn-7-ol(33). Ynone 32 (5.28 g, 5.71 mmol) was taken up in i-PrOH (58 mL). The(S,S)-Noyori catalyst (0.77 g, 1.15 mmol, 20 mol %) was added in oneportion and the solution was stirred overnight. The solvent was removedunder vacuum, and the crude residue was purified by flash chromatographyon silica gel (hexane/EtOAc 97:3), affording propargylic alcohol 33(4.18 g, 79%) as a pale yellow oil: IR (CHCl₃) 3469, 2955, 2856, 1471,1448, 1252, 1084, 836, 774 cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ 7.55 (m, 6H),7.36 (m, 9H), 5.71 (m, 2H), 4.59 (m, 1H), 4.03 (quint, J=3.9 Hz, 1H),3.65 (d, J=3.9 Hz, 2H), 3.58 (dd, J=4.6, 3.2 Hz, 1H), 3.55 (dd, J=10.1,5.1 Hz, 1H), 3.38 (dd, J=9.7, 6.8 Hz, 1H), 2.71 (m, 1H), 2.50 (m, 1H),2.32 (d, J=5.4 Hz, 1H), 1.88 (m, 1H), 1.80 (m, 2H), 1.55 (m, 1H), 1.23(d, J=7.1 Hz, 3H), 1.11 (d, J=6.8 Hz, 3H), 0.98 (m, 34H), 0.20 (s, 3H),0.17 (s, 3H), 0.16 (s, 3H), 0.14 (s, 3H), 0.12 (s, 6H); ¹³C NMR (75 MHz,CDCl₃) δ 144.3, 134.0, 128.6, 127.8, 127.1, 126.9, 88.1, 86.8, 83.0,72.6, 68.3, 65.8, 65.1, 59.5, 41.9, 40.3, 38.7, 33.5, 33.2, 32.1, 26.0,25.9, 18.4, 18.1, 17.7, 17.4, 15.7, 15.3, 14.2, −3.9, −4.0, −4.4, −4.5,−5.3; LRMS (ESI) 949.7 [M+Na]⁺, 413.3, 243.1; HRMS (ESI) calcd forC₅₆H₉₀O₅Si₃Na 949.5994 [M+Na]⁺, found 949.6018; [α]²⁰ _(D) −10.0 (c 1.2,CHCl₃).

(2E,4R,5S,7S,8Z,10S,11R,12S,14R)-5,11,15-tris(tert-Butyldimethylsilyloxy)-4,10,12,14-tetramethyl-1-(trityloxy)pentadeca-2,8-dien-7-ol(34). A catalytic amount of Lindlar catalyst (ca. 200 mg) was added to asolution of alcohol 33 (4.18 g, 4.51 mmol) in toluene (100 mL). Theflask was flushed with H₂ via a balloon several times, then stirredunder an atmosphere of H₂ until starting material was consumed (usually1 h) as indicated by TLC analysis. The mixture was filtered through apad of Celite and concentrated under reduced pressure to afford thealkene 34 as a colorless oil (3.82 g, 91%): IR (CHCl₃) 3436, 2954, 2926,2855, 1461, 1378, 1252, 1061, 836, 773 cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ7.56 (m, 6H), 7.34 (m, 9H), 5.73 (m, 2H), 5.60 (t, J=10.3 Hz, 1H), 5.43(dd, J=10.9, 8.4 Hz, 1H), 4.73 (m, 1H), 3.98 (q, J=5.0 Hz, 1H), 3.68 (d,J=4.1 Hz, 1H), 3.59 (dd, J=9.7, 4.7 Hz, 1H), 3.48 (m, 1H), 3.36 (dd,J=9.0, 7.3 Hz, 1H), 2.79 (m, 1H), 2.58 (m, 1H), 2.23 (br, 1H), 1.78 (m,1H), 1.71 (m, 1H), 1.66 (m, 2H), 1.50 (m, 1H), 1.11 (d, J=6.8 Hz, 3H),1.07 (d, J=6.8 Hz, 3H), 1.00 (m, 34H), 0.22 (s, 3H), 0.18 (s, 3H), 0.14(s, 6H), 0.13 (s, 6H); ¹³C NMR (75 MHz, CDCl₃) δ 144.3, 135.3, 134.6,131.5, 128.7, 127.7, 127.0, 126.8, 86.8, 79.6, 73.0, 68.2, 65.0, 64.7,42.0, 39.6, 38.0, 36.4, 34.9, 33.4, 26.2, 26.0, 25.9, 19.9, 18.4, 18.3,18.1, 18.0, 15.2, 14.5, −3.4, −3.7, −4.2, −4.4, −4.5, −5.4; LRMS (ESI)951.7 [M+Na]⁺, 413.3, 243.1; HRMS (ESI) calcd for C₅₆H₉₂O₅Si₃Na 951.6150[M+Na]⁺, found 951.6172; [α]²⁰ _(D) 1.0 (c 0.62, CHCl₃).

((2E,4R,5S,7S,8Z,10S,11R,12S,14R)-5,7,11,15-tetrakis(tert-Butyldimethylsilyloxy)-4,10,12,14-tetramethylpentadeca-2,8-dienyloxy)triphenylmethane(35). TBSOTf (2.08 mL, 9.07 mmol) was added to a stirred solution of thealcohol 34 (3.82 g, 4.11 mmol) and 2,6-lutidine (1.14 mL, 9.85 mmol) inCH₂Cl₂ (14 mL) at 0° C. The reaction mixture was stirred for 1 h at 0°C. The reaction mixture was quenched by the addition of H₂O (25 mL). Thereaction mixture was extracted with CH₂Cl₂ which was dried over MgSO₄,filtered and the solvent was evaporated under reduced pressure. Theresidue was purified by short column chromatography (hexane/EtOAc 19:1)to obtain 35 (4.27 g, 99%) as a colorless oil: IR (CHCl₃) 2956, 2929,2856, 1471, 1462, 1449, 1255, 1089, 1005, 836, 773, 705 cm⁻¹; ¹H NMR(300 MHz, CDCl₃) δ 7.60 (m, 6H), 7.39 (m, 9H), 5.77 (m, 2H), 5.56 (t,J=10.8 Hz, 1H), 5.42 (dd, J=11.0, 8.2 Hz, 1H), 4.69 (m, 1H), 4.07 (m,1H), 3.71 (d, J=3.8 Hz, 2H), 3.64 (dd, J=9.8, 4.8 Hz, 1H), 3.53 (m, 1H),3.40 (dd, J=9.6, 7.5 Hz, 1H), 2.74 (m, 1H), 2.55 (m, 1H), 1.89 (m, 3H),1.59 (m, 3H), 1.12 (d, J=6.2 Hz, 6H), 1.04 (m, 42H), 0.26 (s, 3H), 0.24(s, 3H), 0.19 (s, 6H), 0.18 (s, 3H), 0.17 (s, 6H), 0.16 (s, 3H); ¹³C NMR(75 MHz, CDCl₃) δ 144.4, 134.5, 132.9, 132.6, 128.7, 127.7, 126.8, 86.8,79.9, 72.3, 68.3, 66.5, 65.1, 64.1, 42.4, 41.6, 37.9, 36.0, 35.3, 33.6,26.3, 26.02, 25.97, 25.7, 19.4, 18.5, 18.4, 18.20, 18.15, 18.1, 15.5,13.3, −2.9, −3.5, −3.7, −4.1, −4.2, −4.3, −5.3; LRMS (ESI) 1065.9[M+Na]⁺, 413.3, 359.3, 328.3, 243.1; HRMS (ESI) calcd for C₆₂H₁₀₆O₅Si₄Na1065.7015 [M+Na]⁺, found 1065.7026; [α]²⁰ _(D) −10.4 (c 0.53, CHCl₃).

(2R,4S,5R,6S,7Z,9S,11S,12R,13E)-5,9,11-tris(tert-Butyldimethylsilyloxy)-2,4,6,12-tetramethyl-15-(trityloxy)pentadeca-7,13-dien-1-ol(36). HF-pyridine in pyridine (40 mL, prepared by slow addition of 12 mLpyridine to 3 mL HF-pyridine complex followed by dilution with 25 mLTHF) was slowly added to a solution of TBS ether 35 (4.27 g, 4.10 mmol)in THF (5 mL) at 0° C. The mixture was stirred for 21 h at 0° C. andquenched with saturated aqueous NaHCO₃ (100 mL). The aqueous layer wasseparated and extracted with Et₂O (3×50 mL). The combined organic layerswere washed with saturated aqueous CuSO₄ (3×50 mL), dried over MgSO₄,filtered and concentrated. Flash column chromatography (EtOAc/hexane1:4) afforded 2.55 g (67%) of the alcohol 36 as a colorless oil: IR(CHCl₃) 3350, 2956, 2928, 2856, 1471, 1448, 1254, 1086, 836, 773, 705cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ 7.52 (m, 6H), 7.32 (m, 9H), 5.68 (m,2H), 5.50 (t, J=10.6 Hz, 1H), 5.35 (dd, J=10.9, 8.5 Hz, 1H), 4.61 (t,J=8.5 Hz, 1H), 4.00 (t, J=8.1 Hz, 1H), 3.62 (d, J=3.2 Hz, 2H), 3.58 (dd,J=10.6, 4.3 Hz, 1H), 3.45 (m, 1H), 3.36 (dd, J=9.9, 7.3 Hz, 1H), 2.66(m, 1H), 2.48 (m, 1H), 1.70 (m, 3H), 1.49 (m, 3H), 1.04 (d, J=6.6 Hz,6H), 0.97 (s, 18H), 0.93 (m, 6H), 0.87 (s, 9H), 0.18 (s, 3H), 0.16 (s,3H), 0.11 (s, 6H), 0.10 (s, 3H), 0.08 (s, 3H); ¹³C NMR (75 MHz, CDCl₃) δ144.3, 134.4, 133.0, 132.1, 128.7, 127.7, 126.8, 86.7, 79.8, 72.3, 67.7,66.5, 65.1, 42.4, 41.5, 37.3, 35.7, 35.5, 33.3, 26.2, 26.0, 25.9, 19.6,18.4, 18.14, 18.06, 17.98, 15.7, 13.2, −2.9, −3.6, −3.7, −4.1, −4.2,−4.3; LRMS (ESI) 951.8 [M+Na]⁺, 771.6, 328.3; HRMS (ESI) calcd forC₅₆H₉₂O₅Si₃Na 951.6150 [M+Na]⁺, found 951.6162; [α]²⁰ _(D) −12.0 (c0.71, CHCl₃).

(2R,4E,6R,8S,9R,10S,11Z,13S,15S,16R,17E)-9,13,15-tris(tert-Butyldimethylsilyloxy)-2-((4S,5S)-2-(4-methoxyphenyl)-5-methyl-1,3-dioxan-4-yl)-6,8,10,16-tetramethyl-19-(trityloxy)nonadeca-4,11,17-trien-3-one(39). The alcohol 36 (2.55 g, 2.75 μmol) in CH₂Cl₂ (30 mL) was treatedwith Dess-Martin periodinane (1.74 g, 4.10 μmol). After 1 h, the mixturewas quenched with saturated aqueous NaHCO₃ (30 mL) and Na₂S₂O₃ (30 mL).The aqueous layer was extracted with Et₂O (2×30 mL) and the combinedextracts were dried over anhydrous MgSO₄. Filtration and concentrationfollowed by short flash column chromatography (hexane/EtOAc 4:1)provided the crude aldehyde as a colorless oil, which was used withoutfurther purification. A mixture of ketophosphonate 38 (1.06 g, 2.75mmol) and Ba(OH)₂ (0.38 g, activated by heating to 100° C. for 1-2 hbefore use) in THF (40 mL) was stirred at room temperature for 30 min. Asolution of the above aldehyde in wet THF (4×1 mL washings, 40:1THF/H₂O) was then added. After stirring for 12 h, the reaction mixturewas diluted with Et₂O (30 mL) and washed with saturated aqueous NaHCO₃(50 mL) and brine (50 mL). The organic solution was dried (MgSO₄),filtered and the solvent was evaporated in vacuo. The residue waschromatographed (hexane/EtOAc 9:1) to yield 39 (2.60 g, 80% for 2 steps)as a colorless oil: IR (CHCl₃) 2956, 2928, 2855, 1688, 1618, 1518, 1471,1461, 1338, 1251, 1080, 1038, 836, 773 cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ7.50 (m, 6H), 7.40 (m, 2H), 7.30 (m, 9H), 6.89 (m, 2H), 6.73 (dd,J=15.6, 8.5 Hz, 1H), 6.29 (d, J=15.6 Hz, 1H), 5.66 (m, 2H), 5.46 (t,J=10.4 Hz, 1H), 5.46 (s, 1H), 5.31 (dd, J=11.0, 8.4 Hz, 1H), 4.58 (t,J=8.1 Hz, 1H), 4.12 (dd, J=11.3, 4.6 Hz, 1H), 3.96 (m, 1H), 3.92 (dd,J=10.0, 4.2 Hz, 1H), 3.80 (s, 3H), 3.60 (d, J=2.8 Hz, 2H), 3.56 (m, 1H),3.39 (t, J=3.3 Hz, 1H), 2.93 (m, 1H), 2.64 (m, 1H), 2.45 (m, 1H), 2.37(m, 1H), 2.01 (m, 1H), 1.61 (m, 1H), 1.54 (m, 2H), 1.50 (m, 1H), 1.44(m, 1H), 1.27 (d, J=7.0 Hz, 3H), 1.06 (d, J=6.6 Hz, 3H), 1.02 (d, J=6.5Hz, 3H), 0.99 (d, J=6.6 Hz, 3H), 0.95 (s, 9H), 0.94 (s, 9H), 0.88 (d,J=6.6 Hz, 3H), 0.84 (s, 9H), 0.79 (d, J=6.7 Hz, 3H), 0.15 (s, 3H), 0.14(s, 3H), 0.07 (s, 3H), 0.06 (s, 3H), 0.05 (s, 3H), 0.03 (s, 3H); ¹³C NMR(75 MHz, CDCl₃) δ 200.7, 159.8, 152.3, 144.3, 134.3, 132.8, 132.1,131.0, 128.6, 127.7, 127.1, 126.8, 126.6, 113.4, 100.8, 86.7, 82.7,80.0, 72.8, 72.1, 66.4, 65.0, 55.2, 47.1, 42.4, 41.4, 39.3, 35.8, 34.7,34.6, 32.2, 26.1, 25.92, 25.86, 20.8, 19.7, 18.3, 18.1, 18.0, 15.0,13.0, 12.4, 10.8, −2.9, −3.7, −3.8, −4.18, −4.25, −4.35; LRMS (ESI)1209.6 [M+Na]⁺, 828.4, 715.3, 449.2, 243.1; HRMS (ESI) calcd forC₇₂H₁₁₀O₈Si₃Na 1209.7406 [M+Na]⁺, found 1209.7474; [α]²⁰ _(D) −6.7 (c0.11, CHCl₃).

(2R,6S,8S,9R,10S,11Z,13S,15S,16R,17E)-9,13,15-tris(tert-Butyldimethylsilyloxy)-2-((4S,5S)-2-(4-methoxyphenyl)-5-methyl-1,3-dioxan-4-yl)-6,8,10,16-tetramethyl-19-(trityloxy)nonadeca-11,17-dien-3-one(40). NiCl₂.6H₂O (0.26 g, 1.09 mmol) then portionwise NaBH₄ (0.17 g,4.49 mmol) were added to a stirred solution of unsaturated ketone 39(2.60 g, 2.19 μmol) in 80 mL of 3:2 MeOH/THF at 0° C. After 1 h, thereaction mixture was evaporated and filtered through Celite using Et₂O(30 mL) as an eluent. The organic phase was concentrated and the residuewas purified by flash chromatography (EtOAc/hexane 1:9) to yield 1.98 gof 40 (76%) as a colorless oil: IR (CHCl₃) 2955, 2927, 2855, 1711, 1614,1518, 1461, 1251, 1076, 835, 773 cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ 7.46(m, 6H), 7.27 (m, 11H), 6.85 (m, 2H), 5.60 (m, 2H), 5.43 (s, 1H), 5.40(m, 1H), 5.27 (m, 1H), 4.52 (m, 1H), 4.11 (dd, J=11.1, 4.7 Hz, 1H), 3.91(m, 2H), 3.78 (s, 3H), 3.55 (m 2H), 3.50 (m, 1H), 3.35 (m, 1H), 2.67 (m,1H), 2.58 (m, 1H), 2.51 (m, 1H), 2.41 (m, 1H), 2.01 (m, 1H), 1.68 (m,3H), 1.41 (m, 5H), 1.23 (d, J=7.1 Hz, 3H), 0.96 (d, J=6.7 Hz, 3H), 0.90(s, 9H), 0.89 (s, 9H), 0.88 (m, 1H), 0.87 (m, 3H), 0.80 (s, 9H), 0.78(m, 6H), 0.10 (s, 3H), 0.08 (s, 3H), 0.04 (s, 3H), 0.03 (s, 6H), 0.01(s, 3H); ¹³C NMR (75 MHz, CDCl₃) δ 211.9, 159.8, 144.5, 144.3, 134.4,132.9, 132.4, 130.9, 128.6, 127.9, 127.8, 127.7, 127.1, 126.8, 113.4,100.8, 86.7, 83.1, 79.9, 72.8, 72.2, 66.4, 65.1, 55.1, 48.3, 42.3, 41.5,41.2, 38.1, 35.7, 35.0, 31.2, 29.8, 29.7, 26.2, 25.92, 25.87, 20.2,19.4, 18.4, 18.1, 18.0, 15.2, 13.2, 12.1, 9.6, −3.0, −3.5, −3.7, −4.2,−4.28, −4.34; LRMS (ESI) 1211.9 (30 mL), 1031.8, 870.4, 684.3, 366.4,243.1; HRMS (ESI) calcd for C₇₂H₁₁₂O₈Si₃Na 1211.7563 (30 mL), found1211.7616; [α]²⁰ _(D) +1.6 (c 0.50, CHCl₃).

(2S,3R,6S,8S,9R,10S,11Z,13S,15S,16R,17E)-9,13,15-tris(tert-Butyldimethylsilyloxy)-2-((4S,5S)-2-(4-methoxyphenyl)-5-methyl-1,3-dioxan-4-yl)-6,8,10,16-tetramethyl-19-(trityloxy)nonadeca-11,17-dien-3-ol(410). NaBH₄ (0.095 g, 2.51 mmol) was added to a solution of ketone 40(1.98 g, 1.67 mmol) in MeOH (28 mL) at 0° C. After stirring for 2 h at0° C., the reaction mixture was evaporated and water (30 mL) was added.The reaction mixture was extracted with ether (2×40 mL) and washed withbrine (50 mL), dried over MgSO₄ and concentrated in vacuo. The residuewas purified by flash chromatography (EtOAc/hexane 1:9) to yield majorproduct the title compound 41β (1.39 g, 70%, less polar) and minorproduct 41α (0.58 g, 28%, more polar) as a colorless oil. 41β:IR (CHCl₃)3398, 2954, 2926, 2854, 1517, 1460, 1251, 1072, 835 cm⁻¹; ¹H NMR (300MHz, CDCl₃) δ 7.50 (m, 6H), 7.39 (m, 2H), 7.33 (m, 9H), 6.89 (m, 2H),5.66 (m, 2H), 5.54 (s, 1H), 5.46 (m, 1H), 5.32 (m, 1H), 4.58 (m, 1H),4.14 (dd, J=11.3, 4.6 Hz, 1H), 3.95 (m, 1H), 3.87 (m, 1H), 3.80 (s, 3H),3.72 (d, J=9.8 Hz, 1H), 3.61 (m, 2H), 3.55 (m, 1H), 3.41 (m, 1H), 3.24(br, 1H), 2.64 (m, 1H), 2.46 (m, 1H), 2.16 (m, 1H), 1.82 (m, 1H), 1.71(m, 2H), 1.53 (m, 5H), 1.35 (m, 2H), 1.06 (d, J=7.2 Hz, 3H), 1.01 (d,J=6.6 Hz, 3H), 0.95 (s, 9H), 0.93 (s, 9H), 0.90 (m, 9H), 0.85 (s, 9H),0.78 (d, J=6.6 Hz, 3H), 0.14 (m, 6H), 0.09 (m, 12H); ¹³C NMR (75 MHz,CDCl₃) δ 160.0, 144.5, 144.3, 134.4, 132.9, 132.4, 130.7, 128.7, 127.9,127.8, 127.7, 127.6, 127.2, 127.1, 126.8, 113.6, 101.2, 89.1, 86.7,80.0, 76.9, 73.1, 72.2, 66.5, 65.1, 42.3, 41.5, 41.4, 37.0, 36.7, 35.1,32.5, 32.1, 30.4, 30.3, 26.2, 25.93, 25.87, 20.4, 19.4, 18.4, 18.1,18.0, 15.4, 13.2, 11.8, 5.4, −3.0, −3.5, −3.7, −4.2, −4.27, −4.33; LRMS(ESI) 1213.7 [M+Na]⁺, 1033.6, 570.9, 364.3, 243.1; HRMS (ESI) calcd forC₇₂H₁₁₄O₈Si₃Na 1213.7719 [M+Na]⁺, found 1213.7861; [α]²⁰ _(D) +6.5 (c0.31, CHCl₃). 41α: IR (CHCl₃) 3540, 2956, 2929, 2855, 1615, 1518, 1461,1383, 1251, 1074, 835, 773 cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ 7.61 (m, 6H),7.51 (m, 2H), 7.44-7.32 (m, 9H), 7.00 (m, 2H), 5.77 (m, 2H), 5.61 (s,1H), 5.55 (m, 1H), 5.45 (m, 1H), 4.71 (m, 1H), 4.24 (dd, J=11.1, 4.5 Hz,11H), 4.07 (m, 1H), 4.01 (m, 1H), 3.88 (s, 3H), 3.73-3.60 (m, 4H), 3.54(m, 1H), 2.76 (m, 1H), 2.56 (m, 1H), 2.49 (m, 1H), 2.24 (m, 1H),1.94-1.78 (m, 4H), 1.72-1.46 (m, 6H), 1.42-1.31 (m, 2H), 1.22 (d, J=7.0Hz, 3H), 1.13 (d, J=5.9 Hz, 3H), 1.06 (s, 18H), 1.03 (m, 6H), 0.96 (s,9H), 0.86 (d, J=6.6 Hz, 3H), 0.27-0.18 (m, 18H); ¹³C NMR (75 MHz, CDCl₃)δ 159.9, 144.4, 144.3, 134.3, 132.9, 132.4, 131.0, 128.6, 127.6, 127.2,126.8, 113.5, 101.0, 86.7, 82.8, 79.8, 74.8, 73.2, 72.2, 66.4, 65.0,55.1, 42.3, 41.5, 37.8, 35.9, 34.9, 33.2, 32.4, 30.3, 30.2, 26.2, 25.92,25.87, 20.4, 19.3, 18.4, 18.1, 18.0, 15.3, 13.2, 11.8, 11.0, −3.0, −3.4,−3.7, −3.9, −4.2, −4.28, −4.34; LRMS (ESI) 1213.9 [M+Na]⁺, 987.7, 659.3,437.2, 243.1; HRMS (ESI) calcd for C₇₂H₁₁₄O₈Si₃Na 1213.7719 [M+Na]⁺,found 1213.7760; [α]²⁰ _(D) +2.3 (c 0.75, CHCl₃).

(4S,5S)-4-((2R,3R,6S,8S,9R,10S,11Z,13S,15S,16R,17E)-3,9,13,15-tetrakis(tert-Butyldimethylsilyloxy)-6,8,10,16-tetramethyl-19-(trityloxy)nonadeca-11,17-dien-2-yl)-2-(4-methoxyphenyl)-5-methyl-1,3-dioxane(42). TBSOTf (0.40 mL, 1.74 mmol) was added to a stirred solution ofalcohol 410 (1.39 g, 1.17 mmol) and 2,6-lutidine (0.27 mL, 2.33 mmol) inCH₂Cl₂ (23 mL) at 0° C. After stirring for 1 h at ambient temperature,the reaction mixture was quenched by the addition of water (50 mL) andextracted by CH₂Cl₂. After drying over MgSO₄, followed by theevaporation of the solution under reduced pressure, the residue waspurified by short column chromatography (hexane/EtOAc 9:1) to yield 42(1.51 g, 99%) as a colorless oil: IR (CHCl₃) 2955, 2928, 2855, 1615,1517, 1461, 1250, 1074, 1039, 835, 773 cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ7.59 (m, 6H), 7.52 (m, 2H), 7.41 (m, 9H), 7.01 (m, 2H), 5.74 (m, 2H),5.57 (s, 1H), 5.50 (m, 1H), 5.43 (m, 1H), 4.67 (m, 1H), 4.25 (dd,J=11.3, 4.6 Hz, 1H), 4.04 (m, 1H), 3.94 (s, 3H), 3.78 (m, 1H), 3.70 (m,3H), 3.49 (m, 1H), 3.16 (m, 1H), 2.72 (m, 1H), 2.54 (m, 1H), 2.18 (m,1H), 2.01 (m, 1H), 1.82 (m, 3H), 1.54 (m, 6H), 1.14 (d, J=6.9 Hz, 3H),1.11 (d, J=6.8 Hz, 3H), 1.10 (d, J=6.5 Hz, 3H), 1.05 (s, 9H), 1.03 (s,9H), 1.02 (s, 12H), 0.98 (d, J=6.3 Hz, 3H), 0.94 (s, 9H), 0.87 (d, J=6.7Hz, 3H), 0.24 (s, 3H), 0.22 (s, 3H), 0.17 (m, 18H); ¹³C NMR (75 MHz,CDCl₃) δ 159.6, 144.5, 144.3, 134.4, 133.1, 132.6, 131.5, 128.6, 127.7,127.6, 127.1, 126.8, 126.7, 113.3, 100.4, 86.7, 81.9, 79.8, 74.9, 73.3,72.2, 66.4, 65.1, 55.1, 42.3, 41.5, 38.8, 35.9, 34.5, 31.3, 31.2, 30.8,30.7, 26.3, 25.99, 25.97, 25.91, 22.6, 20.3, 19.2, 18.5, 18.10, 18.05,15.1, 14.1, 13.1, 12.4, 10.6, −3.0, −3.2, −3.6, −4.2, −4.25, −4.30; LRMS(ESI) 1327.8 [M+Na]⁺, 1147.7, 833.3, 631.3, 429.2, 364.3, 301.1; HRMS(ESI) calcd for C₇₈H₁₂₈O₈Si₄Na 1327.8584 [M+Na]⁺, found 1327.8693; [α]²⁰_(D) +7.6 (c 0.17, CHCl₃).

(2S,3S,4R,5R,8S,10S,11R,12S,13Z,15S,17S,18R,19E)-3-(4-Methoxybenzyloxy)-5,11,15,17-tetrakis(tert-butyldimethylsilyloxy)-2,4,8,10,12,18-hexamethyl-21-(trityloxy)henicosa-13,19-dien-1-ol(43). DIBAL-H (1.0 M in hexane, 11.7 mL, 11.7 mmol) was added dropwiseto a stirred solution of TBS protected acetal 42 (1.53 g, 1.17 mmol) inanhydrous CH₂Cl₂ (2.3 mL) under an atmosphere of N₂ at 0° C. Afterstirring for additional 30 min at 0° C. the reaction mixture wasquenched by the careful addition of aqueous saturated aqueous potassiumsodium tartrate (30 mL). The resulting mixture was stirred for 3 h atroom temperature. The organic layer was separated, and the aqueous layerwas extracted by CH₂Cl₂ (20 mL). The combined organic layers were washedwith brine and dried over MgSO₄ followed by the evaporation of theorganic solution under reduced pressure. The residue was purified bycolumn chromatography (EtOAc/hexane 1:9) to obtain pure 43 (1.35 g, 88%)as a colorless oil: IR (CHCl₃) 3464, 2956, 2929, 2856, 1613, 1514, 1471,1252, 1087, 836, 773 cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ 7.46 (m, 6H), 7.28(m, 11H), 6.88 (m, 2H), 5.61 (m, 2H), 5.39 (m, 1H), 5.28 (m, 1H), 4.57(m, 1H), 4.53 (s, 2H), 3.92 (m, 2H), 3.83 (m, 1H), 3.80 (s, 3H), 3.60(m, 2H), 3.56 (m, 2H), 3.46 (dd, J=6.2, 4.5 Hz, 1H), 3.37 (m, 1H), 3.03(m, 1H), 2.86 (m 1H), 2.59 (m, 1H), 2.41 (m, 1H), 1.93 (m, 1H), 1.88 (m,1H), 1.66 (m, 3H), 1.35 (m, 5H), 1.11 (d, J=7.0 Hz, 3H), 1.01 (d, J=6.8Hz, 3H), 0.97 (d, J=6.8 Hz, 3H), 0.92 (m, 27H), 0.85 (m, 10H), 0.81 (s,9H), 0.11 (s, 3H), 0.09 (s, 3H), 0.07 (s, 3H), 0.06 (s, 6H), 0.05 (s,6H), 0.04 (s, 3H); ¹³C NMR (75 MHz, CDCl₃) δ 159.2, 144.4, 144.3, 134.3,133.0, 132.4, 130.5, 129.1, 128.6, 127.6, 126.7, 113.8, 86.7, 85.4,79.8, 75.1, 73.8, 72.2, 66.4, 65.0, 55.0, 42.3, 41.6, 41.5, 40.5, 37.1,35.8, 34.8, 32.0, 31.9, 30.7, 26.2, 25.94, 25.86, 20.3, 19.2, 18.4,18.1, 18.0, 15.6, 15.2, 13.2, 10.0, −3.0, −3.4, −3.8, −3.9, −4.2, −4.28,4.34, −4.4; LRMS (ESI) 1329.8 [M+Na]⁺, 707.3, 413.2, 243.1; HRMS (ESI)calcd for C₇₈H₁₃₀O₈Si₄Na 1329.8741 [M+Na]⁺, found 1329.8779; [α]²⁰ _(D)−8.9 (c 0.46, CHCl₃).

((2E,4R,5S,7S,8Z,10S,11R,12S,14S,17R,18R,19S,20S,21Z)-19-(4-Methoxybenzyloxy)-5,7,11,17-tetrakis(tert-butyldimethylsilyloxy)-4,10,12,14,18,20-hexamethyltetracosa-2,8,21,23-tetraenyloxy)triphenylmethane(44). The alcohol 43 (1.35 g, 1.03 μmol) in CH₂Cl₂ (20 mL) was treatedwith Dess-Martin periodinane (0.66 g, 1.56 μmol). After 1 h, the mixturewas quenched with saturated aqueous NaHCO₃ (20 mL) and Na₂S₂O₃ (20 mL).The aqueous layer was extracted with Et₂O (2×20 mL) and the combinedextracts were dried over anhydrous MgSO₄. Filtration and concentrationfollowed by short flash column chromatography (hexane/EtOAc 9:1)provided the crude aldehyde as a colorless oil, which was used withoutfurther purification. CrCl₂ (1.06 g, 8.62 mmol) was added to a stirredsolution of the crude aldehyde and 1-bromoallyl trimethylsilane (1.28 g,5.20 mmol) in anhydrous THF (26 mL) under an atmosphere of N₂ at roomtemperature and the mixture was stirred for additional 14 h at ambienttemperature. The reaction mixture was diluted with hexane followed byfiltration through celite. After the evaporation of the solvent underreduced pressure, the residue was purified by short silica gel columnchromatography using EtOAc/hexane (1:9) as eluent. The foregoing productin THF (40 mL) was cooled to 0° C. and NaH (95% w/w, 0.52 g, 20.6 mmol)was added in one portion. The ice bath was removed after 15 min and themixture was stirred for 2 h at ambient temperature. The reaction mixturewas cooled to 0° C., quenched with H₂O (5 mL) and extracted with Et₂O(2×20 mL). The combined organic layers were washed with brine, driedover MgSO₄, filtered and the solvent removed under reduced pressure. Theresidue was purified by column chromatography (hexane/EtOAc 49:1) toobtain 44 (1.17 g, 85% for 3 steps) as a colorless oil: IR (CHCl₃) 2956,2928, 2856, 1614, 1514, 1471, 1462, 1249, 1088, 836, 772 cm⁻¹; ¹H NMR(300 MHz, CDCl₃) δ 7.46 (m, 6H), 7.27 (m, 11H), 6.86 (m, 2H), 6.58 (ddd,J=17.0, 10.6, 10.5 Hz, 1H), 6.00 (t, J=11.0 Hz, 1H), 5.60 (m, 3H), 5.31(m, 2H), 5.17 (d, J=16.9 Hz, 1H), 5.09 (d, J=10.4 Hz, 1H), 4.51 (m, 3H),3.90 (m, 2H), 3.80 (s, 3H), 3.61 (m, 1H), 3.56 (d, J=3.7 Hz, 1H), 3.33(m, 2H), 3.00 (m, 1H), 2.56 (m, 1H), 2.40 (m, 1H), 2.21 (m, 1H), 1.63(m, 3H), 1.38 (m, 2H), 1.27 (m, 3H), 1.21 (m, 2H), 1.10 (d, J=6.7 Hz,3H), 0.96 (m, 3H), 0.93 (s, 9H), 0.91 (s, 9H), 0.89 (s, 9H), 0.86 (m,6H), 0.82 (m, 6H), 0.80 (s, 9H), 0.79 (m, 3H), 0.08 (m, 6H), 0.05 (m,6H), 0.04 (m, 6H), 0.01 (m, 6H); ¹³C NMR (75 MHz, CDCl₃) δ 159.0, 146.2,144.5, 144.4, 134.6, 134.5, 133.1, 132.7, 132.3, 131.4, 129.0, 128.9,128.7, 127.7, 126.8, 117.1, 113.7, 86.8, 84.4, 79.9, 75.0, 72.9, 72.3,66.5, 65.1, 55.2, 42.4, 41.9, 41.6, 40.6, 36.0, 35.6, 35.3, 34.5, 32.5,31.7, 30.5, 26.3, 26.0, 25.9, 20.2, 19.2, 18.8, 18.5, 18.2, 18.1, 15.1,13.3, 9.3, −2.9, −3.0, −3.3, −3.6, −3.7, −4.2, −4.3, −4.4; LRMS (ESI)1351.8 [M+Na]⁺, 1171.7, 1043.7, 889.6, 707.3, 536.1, 453.3, 413.2,359.2; HRMS (ESI) calcd for C₈₁H₁₃₂O₇Si₄Na 1351.8948 [M+Na]⁺, found1351.9012; [α]²⁰ _(D) +1.1 (c 1.7, CHCl₃).

(2E,4R,5S,7S,8Z,10S,11R,12S,14S,17R,18R,19S,20S,21Z)-19-(4-Methoxybenzyloxy)-5,7,11,17-tetrakis(tert-butyldimethylsilyloxy)-4,10,12,14,18,20-hexamethyltetracosa-2,8,21,23-tetraen-1-ol(45). ZnBr₂ (0.41 g) in 1.2 mL of 5:1 CH₂Cl₂/MeOH was added dropwise for30 min to a stirred solution of trityl compound 44 (0.24 g, 0.18 μmol)in 1.4 mL of 6:1 CH₂Cl₂/MeOH at 0° C. After 4 h, the reaction mixturewas quenched with saturated aqueous NaHCO₃ (20 mL) and extracted withEt₂O (2×10 mL). The organic phase were separated, dried with MgSO₄,filtered and concentrated. The residue was purified by flashchromatography (EtOAc/hexane 1:9) to yield 45 (0.15 g, 77%) as acolorless oil: IR (CHCl₃) 3432, 2956, 2856, 1613, 1514, 1471, 1462,1360, 1250, 1082, 835, 773 cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ 7.29 (m, 2H),6.88 (m, 2H), 6.58 (ddd, J=16.9, 10.6, 10.6 Hz, 1H), 6.00 (t, J=11.0 Hz,1H), 5.63 (m, 3H), 5.38 (t, J=11.0 Hz, 1H), 5.27 (dd, J=11.2, 8.3 Hz,1H), 5.17 (d, J=16.8 Hz, 1H), 5.10 (d, J=10.3 Hz, 1H), 4.53 (m, 3H),4.08 (d, J=4.4 Hz, 2H), 3.90 (m, 1H), 3.81 (s, 3H), 3.62 (m, 1H), 3.33(m, 2H), 2.99 (ddd, J=10.0, 6.8, 3.2 Hz, 1H), 2.57 (m, 1H), 2.39 (m,1H), 1.63 (m, 3H), 1.42 (m, 3H), 1.28 (m, 5H), 1.11 (d, J=6.8 Hz, 3H),0.97 (d, J=6.8 Hz, 3H), 0.96 (d, J=6.9 Hz, 3H), 0.93 (s, 9H), 0.91 (s,18H), 0.89 (m, 3H), 0.88 (s, 9H), 0.81 (d, J=6.7 Hz, 3H), 0.80 (d, J=6.2Hz, 3H), 0.10 (s, 3H), 0.09 (s, 3H), 0.08 (s, 6H), 0.06 (s, 3H), 0.05(s, 6H), 0.03 (s, 3H); ¹³C NMR (75 MHz, CDCl₃) δ 159.0, 146.9, 135.2,134.6, 133.0, 132.7, 132.3, 131.4, 129.2, 129.1, 128.9, 127.93, 127.90,127.2, 84.4, 80.0, 75.0, 72.8, 72.2, 66.6, 63.9, 55.2, 42.4, 41.8, 41.7,40.5, 35.9, 35.2, 34.6, 32.6, 31.6, 30.5, 26.3, 25.99, 25.96, 25.93,20.2, 19.2, 18.8, 18.5, 18.2, 18.1, 15.1, 13.2, 9.2, −3.0, −3.3, −3.6,−3.7, −4.2, 4.4, −4.5; LRMS (ESI) 1109.8 [M+Na]⁺, 823.6, 691.5, 559.4;HRMS (ESI) calcd for C₆₂H₁₁₈O₇Si₄Na 1109.7852 [M+Na]⁺, found 1109.7897;[α]²⁰ _(D) +1.6 (c 0.94, CHCl₃).

(2Z,4E,6R,7S,9S,10Z,12S,13R,14S,16S,19R,20R,21S,22S,23Z)-Methyl-21-(4-methoxy-benzyloxy)-7,9,13,19-tetrakis(tert-butyldimethylsilyloxy)-6,12,14,16,20,22-hexamethylhexacosa-2,4,10,23,25-pentaenoate(46). The alcohol 45 (127 mg, 0.117 μmol) in CH₂Cl₂ (4 mL) was treatedwith Dess-Martin periodinane (75 mg, 0.18 μmol). After 1 h, the mixturewas quenched with saturated aqueous NaHCO₃ (5 mL) and Na₂S₂O₃ (5 mL).The aqueous layer was extracted with Et₂O (2×10 mL) and the combinedextracts were dried over anhydrous MgSO₄. Filtration and concentrationfollowed by short flash column chromatography (hexane/EtOAc 9:1)provided the crude aldehyde as a colorless oil, which was used for thenext reaction without further purification. KHMDS (0.28 mL, 0.14 μmol,0.5M solution in toluene) was added dropwise to a stirred solution ofbis(2,2,2-trifluoroethyl)-(methoxycarbonylmethyl) phosphate (0.030 mL,0.14 μmol) and 18-crown-6 (0.15 g, 0.57 mmol) in THF (2.3 mL) at −78° C.Thereafter, the aldehyde in THF (0.5 mL) was added and the solution wasstirred for 4 h at −78° C. The reaction mixture was quenched by additionof a saturated aqueous NH₄Cl (5 mL) and diluted with Et₂O (20 mL). Theorganic phase was washed with brine (30 mL), dried with MgSO₄, filteredand concentrated. The residue was purified by flash chromatography(EtOAc/hexane 1:19) yielding (E,Z)-doubly unsaturated ester 46 (0.12 g,86% for 2 steps) as a colorless oil: IR (CHCl₃) 2955, 2929, 2856, 1722,1514, 1471, 1462, 1250, 1174, 1085, 1041, 836, 773 cm⁻¹; ¹H NMR (300MHz, CDCl₃) δ 7.39 (dd, J=15.4, 11.3 Hz, 1H), 7.29 (m, 2H), 6.88 (m,2H), 6.59 (ddd, J=16.9, 10.8, 10.6 Hz, 1H), 6.55 (t, J=11.3 Hz, 1H),6.01 (t, J=11.0 Hz, 1H), 6.00 (dd, J=15.7, 7.0 Hz, 1H), 5.60 (d, J=11.3Hz, 1H), 5.59 (t, J=10.4 Hz, 1H), 5.39 (t, J=10.4 Hz, 1H), 5.27 (dd,J=11.0, 8.3 Hz, 1H), 5.18 (d, J=16.8 Hz, 1H), 5.11 (d, J=10.3 Hz, 1H),4.54 (m, 3H), 3.96 (m, 1H), 3.81 (s, 3H), 3.74 (s, 3H), 3.63 (m, 1H),3.34 (m, 2H), 3.00 (m, 1H), 2.57 (m, 2H), 1.64 (m, 3H), 1.55 (m, 1H),1.46 (t, J=5.9 Hz, 2H), 1.26 (m, 5H), 1.11 (d, J=6.8 Hz, 3H), 1.05 (d,J=6.7 Hz, 3H), 0.97 (d, J=6.9 Hz, 3H), 0.96 (d, J=7.1 Hz, 3H), 0.94 (s,9H), 0.92 (s, 9H), 0.91 (s, 9H), 0.87 (s, 9H), 0.83 (d, J=6.4 Hz, 3H),0.82 (d, J=6.0 Hz, 3H), 0.13 (s, 3H), 0.11 (s, 3H), 0.10 (s, 3H), 0.09(s, 3H), 0.06 (s, 3H), 0.05 (s, 6H), 0.04 (s, 3H); ¹³C NMR (75 MHz,CDCl₃) δ 166.8, 159.0, 147.3, 145.5, 134.6, 132.9, 132.8, 132.4, 131.4,129.0, 128.9, 126.9, 117.1, 115.5, 113.7, 84.4, 80.0, 75.0, 72.9, 72.1,66.5, 55.2, 50.9, 43.5, 42.5, 41.8, 40.5, 36.0, 35.3, 34.5, 32.5, 31.6,30.5, 26.3, 25.99, 25.96, 25.91, 20.2, 19.2, 18.8, 18.5, 18.2, 18.1,15.0, 13.4, 9.2, −3.0, −3.2, −3.3, −3.6, −3.7, −4.1, −4.4, −4.5; LRMS(ESI) 1163.9 [M+Na]⁺, 1009.8, 684.3, 610.2, 513.4; HRMS (ESI) calcd forC₆₅H₁₂₀O₈Si₄Na 1163.7958 [M+Na]⁺, found 1163.7985; [α]²⁰ _(D) −9.3 (c1.2, CHCl₃).

(2Z,4E,6R,7S,9S,10Z,12S,13R,14S,16S,19R,20R,21S,22S,23Z)-Methyl-7,9,13,19-tetrakis(tert-butyldimethylsilyloxy)-21-hydroxy-6,12,14,16,20,22-hexamethylhexacosa-2,4,10,23,25-pentaenoate(47). The ester 46 (81 mg, 71 μmol) was added to CH₂Cl₂ (2 mL) and H₂O(0.1 mL) and DDQ (20 mg, 88 μmol) was added at 0° C. After 1 h ofstirring at 0° C., the reaction mixture was quenched by adding saturatedaqueous NaHCO₃ (5 mL). The organic phase was washed with saturatedaqueous NaHCO₃ (3×10 mL) and brine, dried over MgSO₄, filtered andconcentrated. Purification by flash column chromatography (EtOAc/hexane1:9) furnished 47 (64 mg, 88%) as a colorless oil: IR (CHCl₃) 3541,2956, 2929, 2856, 1722, 1639, 1471, 1462, 1377, 1360, 1254, 1175, 1086,836, 773 cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ 7.34 (dd, J=15.4, 11.2 Hz, 1H),6.61 (ddd, J=16.8, 10.7, 10.6 Hz, 1H), 6.51 (t, J=11.3 Hz, 1H), 6.06 (t,J=11.0 Hz, 1H), 5.96 (dd, J=15.4, 7.1 Hz, 1H), 5.56 (d, J=11.3 Hz, 1H),5.39 (t, J=10.1 Hz, 1H), 5.38 (t, J=10.3 Hz, 1H), 5.22 (dd, J=11.0, 8.5Hz, 1H), 5.17 (d, J=18.7 Hz, 1H), 5.09 (d, J=10.1 Hz, 1H), 4.50 (m, 1H),3.92 (m, 1H), 3.71 (m, 1H), 3.70 (s, 3H), 3.44 (m, 1H), 3.32 (m, 1H),2.74 (m, 1H), 2.52 (m, 2H), 2.31 (br, 1H), 1.61 (m, 4H), 1.39 (m, 2H),1.31 (m, 2H), 1.26 (m, 3H), 1.00 (d, J=6.7 Hz, 3H), 0.93 (d, J=6.9 Hz,3H), 0.92 (d, J=6.7 Hz, 3H), 0.86 (m, 27H), 0.84 (m, 6H), 0.82 (m, 12H),0.05 (s, 9H), 0.02 (s, 3H), 0.01 (s, 6H), 0.00 (s, 6H); ¹³C NMR (75 MHz,CDCl₃) δ 166.8, 147.3, 145.5, 135.3, 132.7, 132.6, 132.3, 129.9, 126.8,117.7, 115.5, 79.9, 77.6, 76.6, 72.1, 66.5, 51.0, 43.5, 42.4, 41.5,37.7, 36.1, 35.7, 35.0, 32.1, 31.5, 30.6, 26.3, 25.9, 25.9, 20.4, 19.4,18.5, 18.1, 17.9, 17.7, 15.3, 13.3, 6.9, −3.0, −3.4, −3.7, −4.1, −4.2,−4.4; LRMS (ESI) 1043.6 [M+Na]⁺, 889.6, 757.5, 625.4, 393.3; HRMS (ESI)calcd for C₅₇H₁₁₂O₇Si₄Na 1043.7383 [M+Na]⁺, found 1043.7417; [α]²⁰ _(D)−25.3 (c 0.61, CHCl₃).

(2Z,4E,6R,7S,9S,10Z,12S,13R,14S,16S,19R,20R,21S,22S,23Z)-7,9,13,19-tetrakis(tert-Butyldimethylsilyloxy)-21-hydroxy-6,12,14,16,20,22-hexamethylhexacosa-2,4,10,23,25-pentaenoicacid (48). A stirried solution of alcohol 47 (25 mg, 24 μmol) in 3.4 mLof 12:5 EtOH/THF was treated with 1N aqueous KOH (0.24 mL) and themixture was refluxed gently for 3 h. The ethanolic solution wasconcentrated and then diluted with Et₂O (4 mL). After the solution wasacidified to pH3 with 1N aqueous HCl, the organic phase was separatedand aqueous phase was extracted with Et₂O (2×5 mL). The combined organicphase was dried with MgSO₄, filtered, concentrated and the residue wasused without further purification: IR (CHCl₃) 2956, 2929, 2857, 1693,1635, 1600, 1471, 1462, 1254, 1088, 836, 773 cm⁻¹; ¹H NMR (300 MHz,CDCl₃) δ 7.33 (dd, J=15.2, 11.3 Hz, 1H), 6.61 (t, J=11.4 Hz, 1H), 6.61(m, 1H), 6.07 (t, J=11.0 Hz, 1H), 6.02 (dd, J=15.8, 7.2 Hz, 1H), 5.58(d, J=11.3 Hz, 1H), 5.39 (m, 2H), 5.23 (dd, J=11.0, 8.2 Hz, 1H), 5.18(d, J=16.8 Hz, 1H), 5.09 (d, J=10.2 Hz, 1H), 4.50 (m, 1H), 3.92 (m, 1H),3.73 (m, 1H), 3.46 (dd, J=7.3, 2.6 Hz, 1H), 3.34 (m, 1H), 2.78 (m, 1H),2.54 (m, 2H), 1.66 (m, 4H), 1.42 (m, 4H), 1.24 (m, 3H), 1.01 (d, J=6.8Hz, 3H), 0.95 (d, J=6.7 Hz, 3H), 0.94 (d, J=6.7 Hz, 3H), 0.88 (m, 30H),0.84 (m, 15H), 0.09 (s, 3H), 0.07 (s, 3H), 0.06 (s, 6H), 0.02 (s, 6H),0.01 (s, 6H); ¹³C NMR (75 MHz, CDCl₃) δ 171.2, 148.2, 147.3, 135.2,133.2, 132.7, 132.3, 123.0, 127.0, 117.7, 115.2, 79.9, 77.6, 76.5, 72.1,66.4, 43.5, 42.6, 41.6, 37.8, 36.0, 35.8, 34.9, 32.1, 31.5, 30.6, 26.2,25.93, 25.87, 20.3, 19.4, 18.4, 18.10, 18.05, 17.7, 15.3, 13.6, 6.9-3.0,−3.4, −3.7, −4.1, −4.19, −4.24, 4.4; LRMS (ESI) 1029.7 [M+Na]⁺, 875.6,743.6, 611.4, 593.4, 393.3; HRMS (ESI) calcd for C₅₆H₁₁₀O₇Si₄Na1029.7226 [M+Na]⁺, found 1029.7274; [α]²⁰ _(D) −25.7 (c 0.54, CHCl₃).

(8S,10S,14R,20R)-tetrakis(tert-Butyldimethylsilyloxy)-(7R,13S,15S,17S,21S)-pentamethyl-(22S)-((1S)-methylpenta-2,4-dienyl)oxacyclodocosa-3,5,11-trien-2-one(49). A solution of 48 in THF (2 mL) was treated at 0° C. with Et₃N(0.020 mL, 147 μmol) and 2,4,6-trichlorobenzoyl chloride (0.019 mL, 122μmol). The reaction mixture was stirred at 0° C. for 30 min and thenadded to 4-DMAP (12 mL, 0.02 M solution in toluene) at 25° C. Afterstirring for 12 h, the reaction mixture was concentrated, Et₂O (10 mL)was added and the crude was washed with 1N HCl (2×5 mL) and dried overMgSO₄. Purification by flash column chromatography (EtOAc/hexane 1:49)furnished the macrolactone (19 mg, 78% for 2 steps) as a colorless oil:IR (CHCl₃) 2955, 2929, 2857, 1716, 1642, 1474, 1225, 1043, 836, 773cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ 6.98 (dd, J=14.8, 11.3 Hz, 1H), 6.55 (m,1H), 6.52 (t, J=11.2 Hz, 1H), 6.04 (t, J=10.5 Hz, 1H), 6.01 (dd, J=15.4,6.4 Hz, 1H), 5.59 (d, J=11.2 Hz, 1H), 5.58 (m, 1H), 5.38 (t, J=10.6 Hz,1H), 5.33 (dd, J=11.3, 8.1 Hz, 1H), 5.19 (d, J=16.6 Hz, 1H), 5.11 (d,J=10.5 Hz, 1H), 5.06 (dd, J=7.6, 3.7 Hz, 1H), 4.52 (m, 1H), 4.01 (m,1H), 3.63 (m, 1H), 3.19 (d, J=6.2 Hz, 1H), 3.03 (m, 1H), 2.58 (m, 1H),2.52 (m, 2H), 1.81 (m, 4H), 1.45 (m, 3H), 1.25 (m, 3H), 1.09 (m, 3H),1.02 (d, J=6.8 Hz, 3H), 1.01 (d, J=7.0 Hz, 3H), 0.97 (d, J=6.6 Hz, 3H),0.95 (d, J=6.4 Hz, 3H), 0.91 (s, 9H), 0.89 (s, 9H), 0.88 (s, 9H), 0.86(s, 9H), 0.77 (d, J=6.4 Hz, 3H), 0.75 (d, J=6.5 Hz, 3H), 0.10 (s, 3H),0.07 (s, 3H), 0.06 (s, 3H), 0.04 (s, 3H), 0.033 (s, 6H), 0.026 (s, 6H);¹³C NMR (75 MHz, CDCl₃) δ 166.5, 143.1, 141.8, 133.9, 132.7, 131.8,130.2, 129.8, 128.0, 118.4, 118.1, 81.0, 78.0, 70.4, 66.5, 62.5, 43.1,42.3, 41.4, 39.1, 35.2, 34.8, 34.5, 31.6, 30.3, 29.7, 29.3, 26.2, 26.0,25.94, 25.85, 20.2, 19.7, 18.5, 18.24, 18.16, 18.08, 16.2, 14.0, 9.9,−2.7, −3.4, −3.5, −3.8, −3.9, −4.2, −4.3; [α]²⁰ _(D) −18.1 (c 0.24,CHCl₃).

(8S,10S,14R,20R)-Tetrahydroxy-(7R,13S,15S,17S,21S)-pentamethyl-(22S)-((1S)-methylpenta-2,4-dienyl)oxacyclodocosa-3,5,11-trien-2-one(Dictyostatin, 1). A stirred solution of macrolactone 49 (18 mg, 18μmol) in THF (3 mL) at 0° C. was treated with 3N HCl (10 mL, prepared byadding 2.5 mL of conc. HCl to 7.5 mL MeOH). After 24 h at roomtemperature, the reaction mixture was diluted with EtOAc (4 mL) and H₂O(4 mL). The organic phase was saved and the aqueous phase was extractedwith EtOAc (2×4 mL). The combined organic phase was washed withsaturated aqueous NaHCO₃ (10 mL), dried with MgSO₄, filtered andconcentrated. The residue was purified by flash chromatography(EtOAc/hexane 3:2) to yield 1 as a white solid (5.3 mg, 55%): IR (CHCl₃)3406, 2960, 2924, 2872, 1693, 1637, 1461, 1378, 1274, 1181, 1069, 998,738 cm⁻¹; ¹H NMR (600 MHz, CD₃OD) δ 7.21 (dd, J=15.6, 11.1 Hz, 1H), 6.71(ddd, J=16.9, 11.0, 10.6 Hz, 1H), 6.65 (dd, J=11.3, 11.3 Hz, 1H), 6.17(dd, J=15.6, 6.7 Hz, 1H), 6.06 (dd, J=11.1, 11.1 Hz, 1H), 5.56 (d,J=11.3 Hz, 1H), 5.55 (dd, J=11.0, 11.0 Hz, 1H), 5.41 (dd, J=11.1, 8.8Hz, 1H), 5.34 (dd, J=10.7, 10.6 Hz, 1H), 5.25 (dd, J=16.8, 1.8 Hz, 1H),5.15 (d, J=10.1 Hz, 1H), 5.14 (dd, J=7.0, 5.0 Hz, 1H), 4.65 (ddd, J=9.5,9.5, 3.3 Hz, 1H), 4.05 (ddd, J=10.6, 3.7, 2.8 Hz, 1H), 3.17 (ddq,J=10.1, 6.8, 6.6 Hz, 1H), 3.10 (dd, J=8.1, 2.9 Hz, 1H), 2.76 (m, 1H),2.60 (m, 1H), 1.89 (m, 1H), 1.84 (dddd, J=12.9, 11.2, 6.4, 5.4 Hz, 1H),1.60 (m, 1H), 1.58 (m, 1H), 1.54 (m, 1H), 1.50 (ddd, J=14.1, 10.7, 3.5Hz, 1H), 1.42 (ddd, J=14.0, 10.0, 2.7 Hz, 1H), 1.25 (ddd, J=13.7, 10.6,3.6 Hz, 1H), 1.15 (d, J=6.9 Hz, 3H), 1.12 (d, J=7.0 Hz, 3H), 1.10 (m,1H), 1.07 (d, J=6.9 Hz, 3H), 1.01 (d, J=6.8 Hz, 3H), 0.95 (d, J=6.5 Hz,3H), 0.93 (d, J=6.5 Hz, 3H). 0.90 (m, 1H), 0.71 (dddd, J=12.9, 12.8,8.7, 4.9 Hz, 1H); ¹³C NMR (150 MHz, CD₃OD) δ 168.10, 146.42, 144.90,134.87, 134.54, 133.43, 131.32, 131.27, 128.60, 118.58, 118.04, 80.37,78.64, 73.73, 70.41, 65.53, 44.07, 42.28, 40.84, 40.65, 35.84, 35.78,35.33, 32.75, 32.51, 31.23, 21.81, 19.36, 18.08, 15.98, 13.80, 10.41;LRMS (ESI) 555.3 [M+Na]⁺, 449.2, 243.1; HRMS (ESI) calcd for C₃₂H₅₂O₆Na555.3662 [M+Na]⁺, found 555.3665; [α]²⁰ _(D) −22.6 (c 0.27, MeOH).

(2Z,4E,6R,7S,9S,10Z,12S,13R,14S,16S,19R,20S,21S,22S,23Z)-Methyl-7,9,13,19,21-penta-hydroxy-6,12,14,16,20,22-hexamethylhexacosa-2,4,10,23,25-pentaenoate(50). 3N HCl (10 mL, prepared by adding 2.5 mL of conc. HCl to 7.5 mLMeOH) was added to a stirred solution of the macrolactonizationprecursor 48 (23 mg, 23 μmol) in THF (3 mL) at 0° C. After 24 h at roomtemperature, the reaction mixture was diluted with EtOAc (4 mL) and H₂O(4 mL). The organic phase was retained and aqueous phase was extractedwith EtOAc (2×4 mL). The combined organic phase was washed withsaturated aqueous NaHCO₃ (10 mL), dried with MgSO₄, filtered andconcentrated. The residue was purified by flash chromatography(EtOAc/hexane 3:2) to yield the product 50 (4.5 mg, 36%) as a colorlessoil: IR (CHCl₃) 3399, 2917, 2849, 1713, 1635, 1600, 1461, 1439, 1197,1178, 970, 757 cm⁻¹; ¹H NMR (600 MHz, CD₃OD) δ 7.36 (dd, J=15.3, 11.2Hz, 1H), 6.67 (ddd, J=16.9, 11.1, 10.6 Hz, 1H), 6.63 (dd, J=11.3, 11.3Hz, 1H), 6.14 (dd, J=15.4, 8.3 Hz, 1H), 6.03 (dd, J=11.0, 11.0 Hz, 1H),5.59 (d, J=11.4 Hz, 1H), 5.43 (dd, J=10.7, 10.7 Hz, 1H), 5.42 (dd,J=10.8, 9.2 Hz, 1H), 5.32 (dd, J=10.4, 10.4 Hz, 1H), 5.17 (dd, J=16.8,2.0 Hz, 1H), 5.08 (d, J=10.2 Hz, 1H), 4.61 (ddd, J=12.9, 8.5, 4.6 Hz,1H), 3.80 (ddd, J=8.9, 4.4, 4.4 Hz, 1H), 3.69 (s, 3H), 3.63 (m, 1H),3.46 (t, J=5.8 Hz, 1H), 3.13 (dd, J=8.0, 3.2 Hz, 1H), 2.93 (m, 1H), 2.71(m, 1H), 2.38 (m, 1H), 1.73 (m, 1H), 1.56-1.53 (m, 3H), 1.52-1.46 (m,2H), 1.44-1.36 (m, 3H), 1.09 (d, J=6.9 Hz, 3H), 0.98 (d, J=6.8 Hz, 3H),0.96 (d, J=6.6 Hz, 3H), 0.95 (m, 2H), 0.94 (d, J=6.9 Hz, 3H), 0.87 (d,J=6.6 Hz, 3H), 0.86 (d, J=6.8 Hz, 3H); ¹³C NMR (150 MHz, CD₃OD) δ 168.4,148.5, 146.9, 135.7, 135.4, 133.85, 133.82, 130.6, 128.2, 117.7, 116.2,79.2, 78.5, 74.8, 72.4, 65.8, 51.5, 45.1, 43.2, 43.0, 41.0, 37.2, 36.5,34.0, 33.3, 33.1, 31.0, 20.7, 18.6, 18.4, 16.7, 13.8, 7.8; LRMS (ESI)587.5 [M+Na]⁺, 559.2, 485.2, 413.3, 355.1, 212.1; HRMS (ESI) calcd forC₃₃H₅₆O₇Na 587.3924 [M+Na]⁺, found 587.3953; [α]²⁰ _(D) +8.7 (c 0.30,CDCl₃).

(4S,5S)-4-((2R,3S,6S,8S,9R,10S,11Z,13S,15S,16R,17E)-3,9,13,15-tetrakis(tert-Butyldimethylsilyloxy)-6,8,10,16-tetramethyl-19-trityloxynonadeca-11,17-dien-2-yl)-2-(4-methoxyphenyl)-5-methyl-1,3-dioxane(51).

The procedure for 42 was used with 41α (0.58 g, 0.49 mmol), TBSOTf (0.17mL, 0.74 mmol) and 2,6-lutidine (0.11 mL, 0.97 mmol) to yield 0.62 g(97%) of the product by flash column chromatography (EtOAc/hexane 1:9)as a colorless oil: IR (CHCl₃) 2955, 2856, 1615, 1518, 1462, 1385, 1251,1082, 835, 773, 705 cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ 7.55 (m, 6H), 7.49(m, 2H), 7.40-7.27 (m, 9H), 6.96 (m, 2H), 5.72 (m, 2H), 5.53 (m, 1H),5.52 (s, 1H), 5.38 (m, 1H), 4.65 (m, 1H), 4.19 (dd, J=11.0, 4.4 Hz, 1H),4.03 (m, 1H), 3.95 (d, J=8.7 Hz, 1H), 3.86 (m, 1H), 3.84 (s, 3H), 3.66(d, J=3.7 Hz, 2H), 3.56 (t, J=11.1 Hz, 1H), 3.50 (m 1H), 2.71 (m, 1H),2.52 (m, 1H), 2.12 (m, 1H), 1.90-1.79 (m, 2H), 1.75-1.68 (m, 3H),1.61-1.37 (m, 6H), 1.08 (d, J=6.6 Hz, 6H), 1.02-0.91 (m, 36H), 0.81 (d,J=6.5 Hz, 3H), 0.22-0.13 (m, 24H); ¹³C NMR (75 MHz, CDCl₃) δ 159.7,144.5, 134.4, 132.8, 132.6, 131.7, 128.7, 127.7, 127.3, 126.8, 113.4,100.9, 86.7, 81.4, 80.1, 73.4, 72.3, 71.5, 66.5, 65.1, 55.1, 42.4, 41.5,37.9, 35.5, 35.1, 31.3, 30.8, 30.2, 27.9, 26.3, 26.01, 25.99, 25.93,25.7, 20.6, 19.5, 18.4, 18.11, 18.07, 15.4, 13.4, 13.3, 12.2, 9.2, −2.9,−3.5, −3.7, −3.9, −4.1, −4.2, −4.3, −4.9; LRMS (ESI) 1328.0 [M+Na]⁺,782.5, 659.3, 437.2; HRMS (ESI) calcd for C₇₈H₁₂₈O₈Si₄Na 1327.8584[M+Na]⁺, found 1327.8624; [α]²⁰ _(D) +6.1 (c 0.93, CHCl₃).

(2S,3S,4R,5S,8S,10S,11R,12S,13Z,15S,17S,18R,19E)-3-(4-Methoxybenzyloxy))-5,11,15,17-tetrakis(tert-butyldimethylsilyloxy)-2,4,8,10,12,18-hexamethyl-21-trityloxyhenicosa-13,19-dien-1-ol(52). The procedure for 43 was used with 51 (0.62 g, 0.47 mmol) andDIBAL-H (1.0 M in hexane, 4.7 mL, 4.7 mmol) to yield 0.54 g (87%) of theproduct after flash column chromatography (EtOAc/hexane 1:9) as acolorless oil: IR (CHCl₃) 3479, 2955, 2928, 2856, 1613, 1514, 1471,1251, 1084, 835, 773 cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ 7.56-7.52 (m, 6H),7.38-7.33 (m, 9H), 7.30 (m, 2H), 6.94 (m, 2H), 5.72 (m, 2H), 5.52 (m,1H), 5.38 (m, 1H), 4.67 (d, J=10.3 Hz, 1H), 4.65 (m, 1H), 4.60 (d,J=10.4 Hz, 1H), 4.03 (m, 1H), 3.83 (s, 3H), 3.70 (m, 3H), 3.65 (d, J=3.7Hz, 2H), 3.49 (m, 1H), 3.02 (m, 1H), 2.71 (m 1H), 2.52 (m, 1H), 1.91 (m,2H), 1.80-1.64 (m, 3H), 1.60-1.34 (m, 8H), 1.09-0.90 (m, 54H), 0.21-0.12(m, 24H); ¹³C NMR (75 MHz, CDCl₃) δ 159.2, 144.5, 144.3, 134.4, 132.8,132.4, 130.6, 129.0, 128.6, 127.7, 126.8, 113.8, 86.7, 84.7, 80.0, 74.8,74.5, 72.2, 66.5, 66.2, 65.1, 55.1, 42.3, 41.4, 38.7, 35.5, 35.2, 35.0,31.5, 30.9, 30.7, 29.8, 26.2, 26.00, 25.95, 25.89, 20.5, 19.4, 18.4,18.13, 18.08, 18.02, 15.4, 15.2, 13.2, 10.4, −3.0, −3.6, −3.7, −3.8,−4.18, −4.24, −4.3, −4.4; LRMS (ESI) 1329.8 [M+Na]⁺, 782.4, 413.2; HRMS(ESI) calcd for C₇₈H₁₃₀O₈Si₄Na 1329.8741 [M+Na]⁺, found 1329.8782; [α]²⁰_(D) −6.8 (c 0.66, CHCl₃).

((2E,4R,5S,7S,8Z,10S,11R,12S,14S,17S,18R,19S,20S,21Z)-19-(4-Methoxybenzyloxy)-5,7,11,17-tetrakis(tert-butyldimethylsilyloxy)-4,10,12,14,18,20-hexamethyltetracosa-2,8,21,23-tetraenyloxy)triphenylmethane(53). The procedure for 44 was used with 52 (0.54 g, 0.41 μmol) andDess-Martin periodinane (0.26 g, 0.61 μmol), 1-bromoallyltrimethylsilane (0.50 g, 2.60 mmol) and CrCl₂ (0.42 g, 3.42 mmol), NaH(95% w/w, 0.21 g, 8.31 mmol) to yield 0.46 g (83% for 3 steps) of theproduct by flash column chromatography (EtOAc/hexane 1:9) as a colorlessoil: IR (CHCl₃) 2955, 2928, 2856, 1613, 1514, 1462, 1250, 1069, 835,773, 705 cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ 7.58-7.54 (m, 6H), 7.40-7.35(m, 9H), 7.33-7.30 (m, 2H), 6.96-6.93 (m, 2H), 6.69 (ddd, J=16.8, 10.6,10.5 Hz, 1H), 6.12 (t, J=11.0 Hz, 1H), 5.80-5.67 (m, 3H), 5.52 (t,J=10.4 Hz, 1H), 5.40 (m, 1H), 5.28 (d, J=16.8 Hz, 1H), 5.19 (d, J=10.2Hz, 1H), 4.63 (m, 3H), 4.03 (m, 1H), 3.85 (s, 3H), 3.67 (m, 2H), 3.51(m, 1H), 3.38 (m, 1H), 2.96 (m, 1H), 2.72 (m, 1H), 2.53 (m, 1H),1.93-1.74 (m, 2H), 1.66-1.37 (m, 7H), 1.31-1.23 (m, 3H), 1.18 (d, J=6.8Hz, 3H), 1.09 (m, 6H), 1.03-0.92 (m, 45H), 0.23-0.10 (m, 24H); ¹³C NMR(75 MHz, CDCl₃) δ 159.1, 144.5, 144.4, 134.7, 134.5, 133.0, 132.6,132.2, 131.4, 129.1, 129.0, 128.7, 127.7, 126.8, 117.5, 113.7, 86.8,84.6, 79.9, 74.7, 73.6, 72.3, 66.5, 65.1, 55.2, 42.5, 42.4, 41.6, 36.1,35.9, 34.8, 32.0, 30.8, 29.8, 26.3, 26.02, 25.96, 20.5, 19.3, 18.6,18.5, 18.2, 18.1, 15.4, 13.3, 10.5, −2.9, −3.4, −3.7, −4.1, −4.2, −4.3;LRMS (ESI) 1352.0 [M+Na]⁺, 782.5, 647.6, 619.6, 437.2; HRMS (ESI) calcdfor C₈₁H₁₃₂O₇Si₄Na 1351.8948 [M+Na]⁺, found 1351.8987; [α]²⁰ _(D) −8.6(c 1.6, CHCl₃).

(2E,4R,5S,7S,8Z,10S,11R,12S,14S,17S,18R,19S,20S,21Z)-19-(4-Methoxybenzyloxy)-5,7,11,17-tetrakis(tert-butyldimethylsilyloxy)-4,10,12,14,18,20-hexamethyltetracosa-2,8,21,23-tetraen-1-ol(54). The procedure for 45 was used with 53 (0.46 g, 0.35 μmol) andZnBr₂ (0.41 g in 5.8 mL of 24:5 CH₂Cl₂/MeOH) to yield 0.21 g (55%) ofthe product after flash column chromatography (EtOAc/hexane 1:9) as acolorless oil: IR (CHCl₃) 3410, 2956, 2929, 2856, 1614, 1514, 1471,1462, 1251, 1075, 836, 773 cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ 7.28 (m, 2H),6.87 (m, 2H), 6.60 (ddd, J=16.8, 10.7, 10.6 Hz, 1H), 6.03 (t, J=11.0 Hz,1H), 5.67-5.57 (m, 3H), 5.41 (m, 1H), 5.29 (m, 1H), 5.20 (d, J=18.2 Hz,1H), 5.11 (d, J=10.2 Hz, 1H), 4.56 (m, 3H), 4.10 (d, J=4.4 Hz, 1H), 3.93(m, 1H), 3.81 (s, 3H), 3.66-3.57 (m, 2H), 3.40 (dd, J=4.6, 2.6 Hz, 1H),3.28 (dd, J=6.2, 4.2 Hz, 1H), 2.85 (m, 1H), 2.60 (m, 1H), 2.39 (m, 1H),1.79 (m, 1H), 1.70 (m, 1H), 1.66-1.56 (m, 2H), 1.51-1.19 (m, 8H), 1.09(d, J=6.8 Hz, 3H), 0.98 (d, J=6.8 Hz, 3H), 0.97 (d, J=6.9 Hz, 3H),0.92-0.86 (m, 45H), 0.11-0.00 (m, 24H); ¹³C NMR (75 MHz, CDCl₃) δ 159.0,135.2, 134.7, 132.8, 132.7, 132.3, 131.4, 129.2, 129.1, 129.0, 117.4,113.7, 84.6, 80.0, 74.7, 73.6, 72.2, 66.6, 63.9, 63.3, 55.3, 42.4, 41.7,36.1, 35.8, 34.8, 31.9, 30.8, 29.8, 26.3, 26.0, 25.9, 20.5, 19.4, 19.3,18.6, 18.5, 18.1, 15.3, 13.3, 10.5, −3.0, −3.4, −3.7, −4.2, −4.3, −4.5;LRMS (ESI) 1109.9 [M+Na]⁺, 947.8, 782.5, 689.2, 615.2, 541.1, 413.3,306.3; HRMS (ESI) calcd for C₆₂H₁₁₈O₇Si₄Na 1109.7856 [M+Na]⁺, found1109.7902; [α]²⁰ _(D) −12.0 (c 1.7, CHCl₃).

(2Z,4E,6R,7S,9S,10Z,12S,13R,14S,16S,19S,20R,21S,22S,23Z)-Methyl-21-(4-methoxybenzyloxy)-7,9,13,19-tetrakis(tert-butyldimethylsilyloxy)-6,12,14,16,20,22-hexamethylhexacosa-2,4,10,23,25-pentaenoate(55). The procedure for 46 was used with 54 (117 mg, 0.108 μmol) andDess-Martin periodinane (69 mg, 0.16 μmol),bis(2,2,2-trifluoroethyl)-(methoxycarbonylmethyl) phosphate (0.027 mL,0.13 μmol), 18-crown-6 (0.14 g, 0.53 mmol) and KHMDS (0.26 mL, 0.13μmol, 0.5 M solution in toluene) to yield 69 mg (56% for 2 steps) of theproduct after flash column chromatography (EtOAc/hexane 1:19) as acolorless oil: IR (CHCl₃) 2956, 2929, 2856, 1722, 1640, 1514, 1471,1462, 1250, 1174, 1080, 836, 773 cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ 7.44(dd, J=15.2, 11.3 Hz, 1H), 7.28 (m, 2H), 6.88 (m, 2H), 6.60 (ddd,J=16.7, 10.6, 10.5 Hz, 1H), 6.56 (t, J=11.3 Hz, 1H), 6.04 (dd, J=15.5,7.1 Hz, 1H), 6.00 (t, J=11.0 Hz, 1H), 5.62 (m, 2H), 5.42 (m, 1H), 5.27(m, 1H), 5.21 (d, J=16.8 Hz, 1H), 5.11 (d, J=10.3 Hz, 1H), 4.54 (m, 3H),3.97 (m, 1H), 3.81 (s, 3H), 3.74 (s, 3H), 3.60 (m, 1H), 3.40 (m, 1H),3.29 (m, 1H), 2.86 (m, 1H), 2.57 (m, 2H), 1.80-1.67 (m, 3H), 1.55-1.41(m, 4H), 1.40-1.20 (m, 4H), 1.09 (d, J=6.8 Hz, 3H), 1.06 (d, J=6.8 Hz,3H), 0.99 (d, J=6.6 Hz, 3H), 0.98 (d, J=6.7 Hz, 3H), 0.95-0.85 (m, 42H),0.13-0.00 (m, 24H); ¹³C NMR (75 MHz, CDCl₃) δ 166.8, 159.0, 147.3,145.5, 134.7, 132.9, 132.7, 132.3, 131.4, 129.1, 129.0, 126.9, 117.4,115.5, 113.7, 84.6, 80.0, 74.7, 73.6, 72.1, 66.5, 55.3, 51.0, 43.5,42.4, 41.6, 36.1, 35.8, 34.8, 31.9, 30.7, 29.8, 26.3, 26.0, 25.9, 20.5,19.3, 18.6, 18.5, 18.1, 15.3, 13.4, 10.5, −3.0, −3.3, −3.7, −4.10,−4.15, −4.19, −4.3, −4.4; LRMS (ESI) 1163.8 [M+Na]⁺, 1057.7, 782.4,541.1; HRMS (ESI) calcd for C₆₅H₁₂₀O₈Si₄Na 1163.7958 [M+Na]⁺, found1163.8000; [α]²⁰ _(D) −16.7 (c 0.33, CHCl₃).

(2Z,4E,6R,7S,9S,10Z,12S,13R,14S,16S,19S,20R,21S,22S,23Z)-Methyl-7,9,13,19-tetrakis(tert-butyldimethylsilyloxy)-21-hydroxy-6,12,14,16,20,22-hexamethylhexacosa-2,4,10,23,25-pentaenoate(56). The procedure for 47 was used with 55 (68 mg, 60 μmol) and DDQ (15mg, 66 μmol) to yield 56 mg (92%) of the product after flash columnchromatography (EtOAc/hexane 1:9) as a colorless oil: IR (CHCl₃) 3499,2956, 2929, 2856, 1723, 1641, 1471, 1462, 1255, 1175, 1081, 836, 773cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ 7.35 (dd, J=15.2, 11.3 Hz, 1H), 6.64(ddd, J=16.9, 10.6, 10.5 Hz, 1H), 6.52 (t, J=11.3 Hz, 1H), 6.07 (t,J=11.0 Hz, 1H), 5.96 (dd, J=15.5, 7.1 Hz, 1H), 5.56 (d, J=11.3 Hz, 1H),5.44-5.33 (m, 2H), 5.26-5.21 (m, 1H), 5.17 (d, J=16.7 Hz, 1H), 5.07 (d,J=10.1 Hz, 1H), 4.49 (m, 1H), 3.92 (m, 1H), 3.73-3.67 (m, 5H), 3.34 (m,1H), 3.25 (br, 1H), 2.73 (m, 1H), 2.52 (m, 2H), 1.82-1.50 (m, 4H),1.44-1.16 (m, 7H), 1.01 (d, J=6.8 Hz, 3H), 0.97 (d, J=7.1 Hz, 3H), 0.93(d, J=6.9 Hz, 3H), 0.90 (d, J=6.9 Hz, 3H), 0.88-0.81 (m, 42H), 0.08-0.00(m, 24H); ¹³C NMR (75 MHz, CDCl₃) δ 166.8, 147.3, 145.5, 136.5, 132.8,132.7, 132.6, 129.6, 126.8, 117.3, 115.5, 79.8, 78.4, 74.2, 72.1, 66.5,51.0, 43.5, 42.5, 41.4, 36.0, 35.9, 35.8, 35.0, 32.4, 31.9, 30.7, 26.3,26.0, 25.9, 20.4, 19.4, 18.5, 18.12, 18.08, 17.98, 17.4, 15.3, 13.4,10.8, −3.0, −3.4, −3.7, −4.1, −4.2, −4.3, −4.4, −4.8; LRMS (ESI) 1043.7[M+Na]⁺, 889.6, 758.2, 684.2, 610.1; HRMS (ESI) calcd for C₅₇H₁₂O₇Si₄Na1043.7383 [M+Na]⁺, found 1043.7435; [α]²⁰ _(D) −9.4 (c 0.62, CHCl₃).

(2Z,4E,6R,7S,9S,10Z,12S,13R,14S,16S,19S,20R,21S,22S,23Z)-7,9,13,19-tetrakis(tert-Butyldimethylsilyloxy)-21-hydroxy-6,12,14,16,20,22-hexamethylhexacosa-2,4,10,23,25-pentaenoicacid (57). The procedure for 48 was used with 56 (56 mg, 55 μmol) and 1Naqueous KOH (0.54 mL) to yield 57, which was used without furtherpurification: IR (CHCl₃) 2956, 2929, 2857, 1693, 1634, 1471, 1462, 1254,1082, 836, 773 cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ 7.34 (dd, J=15.1, 11.4Hz, 1H), 6.64 (ddd, J=16.5, 10.6, 10.5 Hz, 1H), 6.61 (t, J=11.2 Hz, 1H),6.07 (t, J=11.0 Hz, 1H), 6.01 (dd, J=15.5, 7.2 Hz, 1H), 5.58 (d, J=11.3Hz, 1H), 5.44-5.34 (m, 2H), 5.23 (dd, J=11.0, 8.2 Hz, 1H), 5.17 (d,J=18.0 Hz, 1H), 5.08 (d, J=10.1 Hz, 1H), 4.50 (m, 1H), 3.92 (m, 1H),3.69 (m, 1H), 3.35 (m, 1H), 2.75 (m, 1H), 2.54 (m, 2H), 1.74-1.56 (m,4H), 1.49-1.20 (m, 7H), 1.02 (d, J=6.8 Hz, 3H), 0.98 (d, J=7.2 Hz, 3H),0.94 (d, J=7.0 Hz, 3H), 0.90-0.82 (m, 45H), 0.09-0.01 (m, 24H); ¹³C NMR(75 MHz, CDCl₃) δ 171.1, 148.2, 147.4, 136.4, 132.7, 132.6, 129.6,127.0, 117.4, 115.1, 79.8, 78.4, 74.2, 72.1, 66.5, 43.5, 42.6, 41.5,36.0, 35.9, 35.8, 35.0, 31.9, 30.8, 29.7, 26.3, 26.0, 25.9, 20.4, 19.3,18.5, 18.13, 18.08, 17.97, 17.4, 15.4, 13.7, 10.8, −3.0, −3.4, −3.7,−4.1, −4.2, −4.3, −4.4, −4.8; LRMS (ESI) 1029.8 [M+Na]⁺, 832.3, 758.3,684.3, 610.2, 541.2; HRMS (ESI) calcd for C₅₆H₁₁₀O₇Si₄Na 1029.7226[M+Na]⁺, found 1029.7255; [α]²⁰ _(D) −6.5 (c 0.17, CHCl₃).

(8S,10S,14R,20S)-tetrakis(tert-Butyldimethylsilyloxy)-(7R,13S,15S,17S,21S)-pentamethyl-(22S)-((1S)-methylpenta-2,4-dienyl)-oxacyclodocosa-3,5,11-trien-2-one(58). The procedure for 49 was used with 57, Et₃N (0.046 mL, 33 μmol),2,4,6-trichlorobenzoyl chloride (0.043 mL, 28 μmol) and 4-DMAP (27 mL,0.02 M solution in toluene) to yield 42 mg (78% for 2 steps) of 58 afterflash columnn chromatography (EtOAc/hexane 1:49) as a colorless oil: IR(CHCl₃) 2956, 2929, 2856, 1704, 1638, 1471, 1462, 1378, 1361, 1255,1086, 1044, 1004, 835, 773 cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ 6.98 (dd,J=15.3, 11.3 Hz, 1H), 6.58 (ddd, J=16.9, 10.6, 10.5 Hz, 1H), 6.42 (t,J=11.4 Hz, 1H), 5.94 (t, J=9.2 Hz, 1H), 5.92 (dd, J=9.5, 5.2 Hz, 1H),5.55 (m, 1H), 5.42 (d, J=11.6 Hz, 1H), 5.33-5.21 (m, 3H), 5.12 (d,J=15.1 Hz, 1H), 4.99 (d, J=9.7 Hz, 1H), 4.54 (m, 1H), 3.99 (m, 1H), 3.44(m, 1H), 3.17 (m, 1H), 2.99 (m, 1H), 2.54 (m, 1H), 2.19 (m, 1H), 1.99(m, 1H), 1.61-1.42 (m, 7H), 1.37-1.18 (m, 3H), 1.10 (d, J=6.9 Hz, 3H),1.05 (d, J=7.1 Hz, 3H), 1.00 (d, J=6.3 Hz, 3H), 0.98 (d, J=6.4 Hz, 3H),0.98-0.82 (m, 36H), 0.79 (d, J=6.6 Hz, 3H), 0.66 (d, J=6.7 Hz, 3H),0.11-0.01 (m, 24H); 13_(c) NMR (75 MHz, CDCl₃) δ 166.4, 146.5, 143.9,134.3, 132.7, 132.2, 130.8, 129.8, 127.9, 117.4, 117.1, 81.6, 78.0,77.1, 73.0, 66.7, 46.9, 45.7, 41.2, 37.5, 35.8, 35.1, 34.5, 31.1, 29.7,26.2, 26.1, 26.0, 25.9, 20.5, 19.5, 19.1, 18.5, 18.4, 18.2, 17.9, 17.3,16.9, 7.9, −2.6, −3.4, −3.5, −4.3, −4.4, 4.6; LRMS (ESI) 1011.7 [M+Na]⁺,803.5, 633.1, 544.2, 413.2; HRMS (ESI) calcd for C₅₆H₁₀₈O₆Si₄Na1011.7121 [M+Na]⁺, found 1011.7164; [α]²⁰ _(D) −61.6 (c 2.8, CHCl₃).

(8S,10S,14R,20S)-Tetrahydroxy-(7R,13S,15S,17S,21S)-pentamethyl-(22S)-((1S)-methylpenta-2,4-dienyl)-oxacyclodocosa-3,5,11-trien-2-one(59). 3N HCl (10 mL, prepared by adding 2.5 mL of conc. HCl to 7.5 mLMeOH) was added to a stirred solution of macrolactone 58 (42 mg, 42μmol) in THF (3 mL) at 0° C. After 24 h at room temperature, thereaction mixture was diluted with EtOAc (4 mL) and H₂O (4 mL). Theorganic phase was retained and the aqueous phase was extracted withEtOAc (2×4 mL). The combined organic phase was washed with saturatedaqueous NaHCO₃ (10 mL), dried with MgSO₄, filtered and concentrated. Theresidue was purified by flash chromatography (EtOAc/hexane 3:2) to yield59 (7.9 mg, 35%) as a colorless oil: IR (CHCl₃) 3415, 2961, 2917, 2849,1681, 1637, 1461, 1279, 1067, 965, 758 cm⁻¹; ¹H NMR (600 MHz, CD₃OD) δ7.05 (dd, J=15.3, 11.3 Hz, 1H), 6.65 (ddd, J=16.9, 10.2, 10.1 Hz, 1H),6.53 (dd, J=11.5, 11.5 Hz, 1H), 5.97 (dd, J=15.3, 9.5 Hz, 1H), 5.94 (dd,J=11.0, 11.0 Hz, 1H), 5.60 (dd, J=10.8, 9.6 Hz, 1H), 5.41 (d, J=11.5 Hz,1H), 5.20 (dd, J=10.5, 10.3 Hz, 1H), 5.11 (dd, J=16.9, 2.0 Hz, 1H), 5.10(dd, J=9.7, 2.1 Hz, 1H), 5.01 (d, J=10.1 Hz, 1H), 4.60 (ddd, J=10.1,9.7, 2.7 Hz, 1H), 3.94 (ddd, J=11.0, 2.1, 2.0 Hz, 1H), 3.38 (ddd, J=9.8,3.0, 2.0 Hz, 1H), 3.09 (ddq, J=13.0, 7.0, 4.9 Hz, 1H), 3.01 (dd, J=8.3,2.7 Hz, 1H), 2.70 (m, 1H), 2.23 (ddd, J=9.3, 7.0, 2.4 Hz, 1H), 2.07(ddd, J=7.0, 2.6, 2.5 Hz, 1H), 1.67 (m, 2H), 1.56 (ddd, J=14.0, 10.9,2.9 Hz, 1H), 1.51 (m, 1H), 1.47 (ddd, J=14.1, 10.5, 1.9 Hz, 1H), 1.17(d, J=6.9 Hz, 3H), 1.13 (m, 1H), 1.11 (d, J=7.1 Hz, 3H), 1.09 (d, J=7.0Hz, 3H), 1.02 (d, J=6.7 Hz, 3H), 1.00 (m, 1H), 0.93 (d, J=6.4 Hz, 3H),0.92 (m, 1H), 0.78 (m, 1H), 0.76 (d, J=6.7 Hz, 3H). 0.74 (m, 1H); ¹³CNMR (150 MHz, CD₃OD) δ 168.3, 147.6, 145.3, 135.4, 134.3, 133.5, 131.3,131.0, 130.1, 118.1, 81.2, 79.9, 77.6, 72.0, 65.1, 45.9, 44.8, 42.4,38.7, 36.0, 35.6, 31.8, 29.8, 27.8, 22.2, 19.8, 18.4, 17.6, 16.4, 9.1;LRMS (ESI) 555.3 [M+Na]⁺, 443.2; HRMS (ESI) calcd for C₃₂H₅₂O₆ 555.3662[M+Na]⁺, found 555.3655; [α]²⁰ _(D) −76.2 (c 0.45, MeOH).

(4S,5R,6S)-7-(4-Methoxybenzyloxy)-5-(tert-butyldimethylsilyloxy)-4,6-dimethylheptan-1-ol(61). DIBAL-H (19.8 mL, 19.8 mmol, 1.0 M solution in hexane) was addedat −78° C. dropwise to ester 60 (3.59 g. 7.94 μmol) in CH₂Cl₂ (40 mL).After stirring for 1 h, the reaction mixture was quenched by addition ofEtOAc (5 mL) and saturated aqueous sodium potassium tartrate (80 mL),followed by vigorous stirring for 4 h. The aqueous phase was extractedwith CH₂Cl₂ (3×20 mL) and the combined organic layers were washed withbrine (40 mL). After drying over MgSO₄, filtration and evaporation undervacuum, flash column chromatography (hexane/EtOAc 3:7) provided 60 (2.51g, 77%) as a colorless oil: IR (CHCl₃) 3387, 2934, 2856, 1612, 1513,1472, 1462, 1360, 1302, 1249, 1172, 1039, 836, 773 cm⁻¹; ¹H NMR (300MHz, CDCl₃)

7.42-7.38 (m, 2H), 7.03-6.98 (m, 2H), 4.58 (d, J=11.6 Hz, 1H), 4.53 (d,J=11.6 Hz, 1H), 3.92 (s, 3H), 3.70 (d, J=6.6 Hz, 2H), 3.64 (m, 2H), 3.38(dd, J=8.8, 7.6 Hz, 1H), 2.31 (br, 1H), 2.16-2.03 (m, 1H), 1.78-1.66 (m,2H), 1.65-1.50 (m, 2H), 1.38-1.28 (m, 1H), 1.09 (d, J=6.9 Hz, 3H), 1.03(s, 9H), 1.01 (d, J=6.9 Hz, 3H), 0.18 (s, 3H), 0.17 (s, 3H); ¹³C NMR (75MHz, CDCl₃) δ 159.0, 130.7, 129.0, 113.6, 77.4, 72.6, 72.5, 62.8, 55.1,37.8, 36.1, 30.8, 30.4, 26.0, 18.3, 15.2, 14.5, −3.8, −4.2; LRMS (ESI)433.3 [M+Na]⁺; HRMS (ESI) calcd for C₂₃H₄₂O₄SiNa433.2750 [M+Na]⁺, found433.2765; [α]²⁰ _(D) −10.2 (c 1.0, CHCl₃).

1-(((2S,3R,4S)-3,7-bis(tert-Butyldimethylsilyloxy)-2,4-dimethylheptyloxy)methyl)-4-methoxybenzene(62). TBSCl (0.92 g, 6.11 mmol) was added to a solution of above alcohol61 (2.51 g, 6.11 mmol) and imidazole (0.46 g, 6.76 mmol) in CH₂Cl₂ (20mL). The resulting slurry was stirred for 1 h at room temperature. Theorganic phase was washed with water (100 mL) and brine (2×100 mL). Afterdrying over MgSO₄, filtration and evaporation under vacuum, the residuewas used directly in next step: IR (CHCl₃) 2930, 2856, 1613, 1513, 1471,1360, 1250, 1098, 1040, 835, 773 cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ7.29-7.26 (m, 2H), 6.90-6.88 (m, 2H), 4.46 (d, J=11.6 Hz, 1H), 4.42 (d,J=11.6 Hz, 1H), 3.81 (s, 3H), 3.62 (t, J=6.3 Hz, 2H), 3.58-3.52 (m, 2H),3.28 (dd, J=8.8, 7.7 Hz, 1H), 2.02-1.94 (m, 1H), 1.66-1.54 (m, 2H),1.52-1.39 (m, 2H), 1.28-1.18 (m, 1H), 0.99 (d, J=6.9 Hz, 3H), 0.94 (s,9H), 0.92 (s, 9H), 0.89 (d, J=6.8 Hz, 3H), 0.09 (s, 6H), 0.07 (s, 3H),0.06 (3H); ¹³C NMR (75 MHz, CDCl₃) δ 159.0, 130.9, 129.0, 113.6, 77.5,72.8, 72.6, 63.4, 55.1, 38.0, 36.3, 31.1, 30.8, 26.1, 25.9, 18.4, 18.3,15.2, 14.4, −3.8, −4.1, −5.3; LRMS (ESI) 547.4 [M+Na]⁺ 413.3, 212.1;HRMS (ESI) calcd for C₂₉H₅₆O₄Si₂Na 547.3615 [M+Na]⁺, found 547.3638;[α]²⁰ _(D) −9.9 (c 2.5, CHCl₃).

(2S,3R,4S)-3,7-bis(tert-Butyldimethylsilyloxy)-2,4-dimethylheptan-1-ol(63). The PMB alcohol 62 (6.11 mmol) was added to CH₂Cl₂ (19 mL) thenH₂O (1 mL) and DDQ (1.80 g, 7.93 μmol) were added. After 1 h ofstirring, the reaction was quenched by adding saturated aqueous NaHCO₃(100 mL). The organic phase was washed with saturated aqueous NaHCO₃(3×100 mL) and brine, dried over MgSO₄ filtered and concentrated.Purification by flash column chromatography (EtOAc/hexane 1:9) furnished63 (2.23 g, 90%) as a colorless oil: IR (CHCl₃) 3403, 2928, 2856, 1472,1463, 1388, 1256, 1100, 836, 773 cm⁻¹; ¹H NMR (300 MHz, CDCl₃)

3.59-3.50 (m, 4H), 3.46 (dd, J=5.5, 3.7 Hz, 1H), 1.83-1.75 (m, 1H),1.62-1.52 (m, 2H), 1.49-1.35 (m, 2H), 1.18-1.05 (m, 1H), 0.91 (d, J=7.0Hz, 3H), 0.87-0.84 (m, 21H), 0.05 (s, 3H), 0.03 (s, 3H), 0.00 (s, 6H);¹³C NMR (75 MHz, CDCl₃) δ 80.4, 65.8, 63.3, 38.1, 37.8, 31.1, 29.6,26.0, 25.9, 18.2, 15.9, 14.9, −4.0, −4.2, −5.4; LRMS (ESI) 427.3[M+Na]+, 256.8, 212.1; HRMS (ESI) calcd for C₂₁H₄₈O₃Si₂Na 427.3040[M+Na]+, found 427.3050; [α]²⁰ _(D) −14.0 (c 0.6, CHCl₃).

(3S,4R,5S)-4,8-bis(tert-Butyldimethylsilyloxy)-3,5-dimethyloct-1-yne(64). Sulfur trioxide pyridine complex (2.63 g, 16.5 mmol) was added toa stirred solution of alcohol 63 (2.23 g, 5.51 mmol) and triethylamine(2.25 mL, 16.5 mmol) in anhydrous CH₂Cl₂ (12 mL) and DMSO (22 mL) at 0°C. The reaction mixture was stirred at ambient temperature for 1 h. Themixture was diluted with Et₂O (100 mL) and washed with 0.5N aqueous HCl(50 mL) and brine (10 mL). The separated organic layer was dried overMgSO₄. Filtration and concentration followed by short flash columnchromatography (hexane/EtOAc 4:1) provided the crude aldehyde as acolorless oil, which was used without further purification. A mixture ofcarbon tetrabromide (3.65 g, 11.0 mmol) and triphenylphosphine (5.78 g,22.0 mmol) in CH₂Cl₂ (50 mL) was stirred at 0° C. for 10 min. A solutionof the crude aldehyde and 2,6-lutidine (1.27 mL, 11.0 mmol) in CH₂Cl₂ (5mL) was transferred via cannula to the reaction mixture. The reactionwas stirred for an additional 2 h at 0° C., then quenched with asaturated aqueous NH₄Cl (20 mL). The layers were separated and theaqueous layer was extracted with CH₂Cl₂ (2×20 mL). The combined layerswere dried over MgSO₄, filtered and concentrated in vacuo. Flash columnchromatography over silica gel (EtOAc/hexane 1:19) afforded the vinyldibromide as a colorless oil. The vinyl dibromide in THF (18 mL) wascooled to −78° C. and treated with n-BuLi (8.6 mL, 13.8 mmol, 1.6 Msolution in hexane). The reaction was stirred for 1 h at −78° C., warmedto 20° C. and stirred an additional 1 h. Saturated aqueous NH₄Cl (5 mL)was added, the layers were separated and the aqueous layer was extractedwith Et₂O. The combined organic layer was dried over MgSO₄, filtered andconcentrated in vacuo. Purification by flash column chromatography(EtOAc/hexane 1:9) furnished 64 (1.20 g, 55% for 3 steps) as a colorlessoil: IR (CHCl₃) 3313, 2930, 2857, 1472, 1463, 1387, 1361, 1254, 1099,835, 774, 627 cm⁻¹; ¹H NMR (300 MHz, CDCl₃)

3.74 (m, 2H), 3.66 (dd, J=4.7, 3.8 Hz, 1H), 2.74 (m, 1H), 2.14 (d, J=2.5Hz, 1H), 1.85 (m, 1H), 1.74-1.56 (m, 4H), 1.31 (d, J=7.1 Hz, 3H),1.05-1.01 (m, 18H), 0.23 (s, 3H), 0.20 (s, 3H), 0.18 (s, 6H); ¹³C NMR(75 MHz, CDCl₃) δ 87.4, 77.9, 69.9, 63.4, 36.5, 31.5, 31.0, 30.7, 26.1,26.0, 18.4, 18.3, 17.5, 15.0, −3.9, −5.3; LRMS (ESI) 421.3 [M+Na]⁺,372.8, 359.3, 256.8, 212.1; HRMS (ESI) calcd for C₂₂H₄₆O₂Si₂Na 421.2934[M+Na]⁺, found 421.2942; [α]²⁰ _(D) −5.3 (c 1.3, CHCl₃).

(4R,5S,10S,11R,12S,E)-5,11,15-tris(tert-Butyldimethylsilyloxy)-4,10,12-trimethyl-1-trityloxypentadec-2-en-8-yn-7-one.The procedure for 32 was used with 15 (1.31 g, 2.28 μmol), 64 (1.20 g,3.01 mmol) and n-BuLi (1.88 mL, 1.20 mmol) to yield the ynone (1.79 g,86%) after flash column chromatography (EtOAc/hexane 1:19) as acolorless oil: IR (CHCl₃) 2929, 2856, 2209, 1675, 1471, 1462, 1385,1254, 1093, 836, 775, 705 cm⁻¹; ¹H NMR (300 MHz, CDCl₃)

7.56-7.53 (m, 6H), 7.38-7.25 (m, 9H), 5.79 (dd, J=15.6, 7.2 Hz, 1H),5.67 (dt, J=15.6, 4.9 Hz, 1H), 4.36 (m, 1H), 3.69-3.66 (m, 4H), 3.63 (t,J=4.1 Hz, 1H), 2.86 (m, 1H), 2.72 (m, 1H), 2.45 (m, 1H), 1.76 (m, 1H),1.67-1.51 (m, 3H), 1.34 (m, 1H), 1.29 (d, J=7.1 Hz, 3H), 1.14 (d, J=6.8Hz, 3H), 1.00-0.97 (m, 28H), 0.18-0.13 (m, 18H); ¹³C NMR (75 MHz, CDCl₃)δ 186.0, 144.2, 132.8, 128.6, 127.9, 127.7, 126.8, 96.7, 86.8, 83.1,77.8, 71.6, 64.8, 63.2, 50.1, 42.3, 37.2, 31.7, 30.9, 30.2, 26.0, 25.9,25.8, 18.3, 18.2, 18.0, 17.3, 15.4, 14.8, −3.9, −4.1, 4.6, −4.7, −5.3;LRMS (ESI) 933.6 [M+Na]⁺, 795.5, 665.2, 496.1, 413.2, 243.1; HRMS (ESI)calcd for C₅₅H₈₆O₅Si₃Na 933.5681 [M+Na]⁺, found 933.5692; [α]²⁰ _(D)−90.5 (c 0.55, CHCl₃).

(4R,5S,7S,10S,11R,12S,2E)-5,11,15-tris(tert-Butyldimethylsilyloxy)-4,10,12-trimethyl-1-trityloxypentadec-2-en-8-yn-7-ol(65). The procedure for 33 was used with the above ynone (1.77 g, 1.94μmol), (S,S)-Noyori catalyst (0.26 g, 20 mol %) and i-PrOH (19 mL) toyield 65 (1.69 g, 95%) after flash column chromatography (EtOAc/hexane1:19) as a pale yellow oil: IR (CHCl₃) 3464, 2929, 2856, 1471, 1448,1386, 1254, 1090, 836, 774, 705 cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ7.56-7.54 (m, 6H), 7.39-7.26 (m, 9H), 5.78 (dd, J=15.7, 6.4 Hz, 1H),5.68 (dt, J=15.6, 4.9 Hz, 1H), 4.57 (m, 1H), 4.06 (m, 1H), 3.71-3.67 (m,4H), 3.62 (t, J=4.0 Hz, 1H), 2.74 (m, 1H), 2.50 (m, 1H), 2.46 (d, J=5.4Hz, 1H), 1.82 (m, 3H), 1.72-1.54 (m, 3H), 1.36 (m, 1H), 1.24 (d, J=7.1Hz, 3H), 1.13 (d, J=6.8 Hz, 3H), 1.04-0.94 (m, 27H), 0.21-0.14 (m, 18H);¹³C NMR (75 MHz, CDCl₃) δ 144.3, 133.8, 128.6, 127.7, 127.2, 126.8,87.8, 86.8, 83.1, 77.7, 72.5, 65.0, 63.5, 59.4, 41.9, 40.6, 36.4, 31.7,30.7, 26.01, 25.96, 25.9, 18.3, 18.0, 17.4, 15.2, 14.5, −4.0, −4.1,−4.4, −4.5, −5.3; LRMS (ESI) 935.4 [M+Na]⁺; HRMS (ESI) calcd forC₅₅H₈₈O₅Si₃Na 935.5837 [M+Na]⁺, found 935.5851; [α]²⁰ _(D) −10.5 (c0.86, CHCl₃).

(2E,4R,5S,7S,8Z,10S,11R,12S)-5,11,15-tris(tert-Butyldimethylsilyloxy)-4,10,12-trimethyl-1-(trityloxy)pentadeca-2,8-dien-7-ol(66). The procedure for 34 was used with alkyne 65 (1.69 g, 1.85 μmol)and Lindlar catalyst (ca. 200 mg) to yield 66 (1.70 g, quantitative) asa pale yellow oil: IR (CHCl₃) 3477, 2955, 2856, 1471, 1448, 1386, 1254,1057, 835, 773, 705 cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ 7.63-7.60 (m, 6H),7.43-7.27 (m, 9H), 5.88-5.77 (m, 2H), 5.70 (t, J=10.1 Hz, 1H), 5.49 (dd,J=10.6, 8.4 Hz, 1H), 4.78 (m, 1H), 4.06 (m, 1H), 3.76-3.72 (m, 4H), 3.58(t, J=3.6 Hz, 1H), 2.89 (m, 1H), 2.63 (m, 1H), 2.20 (d, J=2.8 Hz, 1H),1.73-1.48 (m, 7H), 1.18 (d, J=6.9 Hz, 3H), 1.15 (d, J=7.0 Hz, 3H),1.08-1.02 (m, 27H), 0.29-0.20 (m, 18H); ¹³C NMR (75 MHz, CDCl₃) δ 144.3,134.9, 134.4, 131.5, 128.6, 127.7, 127.0, 126.8, 86.7, 79.8, 72.8, 65.0,64.7, 63.5, 42.1, 39.7, 37.9, 35.9, 31.4, 29.9, 26.2, 26.0, 25.9, 20.1,18.4, 18.3, 18.0, 14.9, 14.5, −3.6, −3.8, −4.5, −4.6, −5.3; LRMS (ESI)937.5 [M+Na]⁺;

HRMS (ESI) calcd for C₅₅H₉₀O₅Si₃Na 937.5994 [M+Na]⁺, found 937.6016;[α]²⁰ _(D) +2.1 (c 0.92, CHCl₃).

((2E,4R,5S,7S,8Z,10S,11R,12S)-5,7,11,15-tetrakis(tert-Butyldimethylsilyloxy)-4,10,12-trimethylpentadeca-2,8-dienyloxy)triphenylmethane(67). The procedure for 35 was used with alcohol 66 (1.70 g, 1.85 μmol),TBSOTf (0.94 mL, 4.07 mmol) and 2,6-lutidine (0.51 mL, 4.44 mmol) toyield 67 (1.82 g, 96%) by flash column chromatography (EtOAc/hexane1:19) as a colorless oil: IR (CHCl₃) 2956, 2856, 1471, 1448, 1254, 1092,1004, 836, 773 cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ 7.77-7.75 (m, 6H),7.57-7.47 (m, 9H), 6.02-5.87 (m, 2H), 5.76 (t, J=10.8 Hz, 1H), 5.61 (dd,J=10.8, 8.5 Hz, 1H), 4.88 (m, 1H), 4.24 (m, 1H), 3.88 (m, 4H), 3.75 (m,1H), 2.94 (m, 1H), 2.73 (m, 1H), 1.83 (m, 2H), 1.75 (m, 2H), 1.57 (m,1H), 1.46-1.41 (m, 2H), 1.31 (d, J=6.8 Hz, 3H), 1.30 (d, J=6.3 Hz, 3H),1.24-1.13 (m, 39H), 0.44-0.34 (m, 24H); ¹³C NMR (75 MHz, CDCl₃) δ 144.4,134.4, 132.9, 132.2, 128.7, 127.7, 126.8, 86.8, 80.2, 72.3, 66.6, 65.1,63.6, 42.4, 41.6, 38.4, 35.7, 31.6, 29.9, 26.3, 26.0, 19.6, 18.5, 18.4,18.2, 15.1, 13.2, −2.9, −3.6, −3.7, −4.2, −5.2; LRMS (ESI) 1051.6[M+Na]⁺, 918.6, 769.5, 637.4, 413.2; HRMS (ESI) calcd for C₆₁H₁₀₄O₅Si₄Na1051.6859 [M+Na]⁺, found 1051.6848 [α]²⁰ _(D) −8.3 (c 2.4, CHCl₃).

(4S,5R,6S,7Z,9S,11S,12R,13E)-5,9,11-tris(tert-Butyldimethylsilyloxy)-4,6,12-trimethyl-15-(trityloxy)pentadeca-7,13-dien-1-ol(68). The procedure for 36 was used with 67 (1.82 g, 1.77 μmol) andHF-pyridine in pyridine (100 mL) to yield 68 (1.15 g, 71%) by flashcolumn chromatography (EtOAc/Hexane 1:9) as a colorless oil: IR (CHCl₃)3349, 2956, 2929, 2856, 1471, 1448, 1254, 1060, 836, 773, 705 cm⁻¹; ¹HNMR (300 MHz, CDCl₃) δ 7.58-7.55 (m, 6H), 7.39-7.27 (m, 9H), 5.81-5.65(m, 2H), 5.56 (t, J=10.7 Hz, 1H), 5.41 (dd, J=11.0, 8.4 Hz, 1H), 4.67(m, 1H), 4.05 (m, 1H), 3.69-3.63 (m, 4H), 3.53 (m, 1H), 2.73 (m, 1H),2.52 (m, 1H), 1.64 (m, 3H), 1.58-1.48 (m, 2H), 1.30-1.20 (m, 2H), 1.11(d, J=6.8 Hz, 3H), 1.10 (d, J=6.6 Hz, 3H), 1.03-0.92 (m, 30H), 0.23-0.14(m, 18H); ¹³C NMR (75 MHz, CDCl₃) δ 144.3, 134.3, 132.9, 132.0, 128.6,127.7, 126.8, 86.7, 80.1, 72.3, 66.4, 65.0, 63.1, 42.4, 41.7, 38.2,35.5, 31.2, 29.5, 26.2, 25.95, 25.89, 19.6, 18.4, 18.1, 18.0, 15.1,13.3, −2.9, −3.7, −3.8, −4.17, −4.24, −4.3; LRMS (ESI) 937.6 [M+Na]⁺;HRMS (ESI) calcd for C₅₅H₉₀O₅Si₃Na 937.5994 [M+Na]⁺, found 937.6035;[α]²⁰ _(D) −10.8 (c 0.84, CHCl₃).

(2R,4E,8S,9R,10S,11Z,13S,15S,16R,17E)-9,13,15-tris(tert-Butyldimethylsilyloxy)-2-((4S,5S)-2-(4-methoxyphenyl)-5-methyl-1,3-dioxan-4-yl)-8,10,16-trimethyl-19-(trityloxy)nonadeca-4,11,17-trien-3-one(69). The procedure for 39 was used with alcohol 68 (1.15 g, 1.26 μmol),Dess-Martin reagent (0.80 g, 1.89 mmol) and Ba(OH)₂ (0.17 g, 1.01 mmol)and 38 (0.49 g, 1.27 mmol) to yield 69 (1.22 g, 83%) after flash columnchromatography (EtOAc/hexane 1:9) as a colorless oil: IR (CHCl₃) 2956,2929, 2856, 1693, 1618, 1518, 1461, 1388, 1251, 1080,836,773 cm⁻¹; ¹HNMR (300 MHz, CDCl₃) δ 7.70-7.68 (m, 6H), 7.60-7.57 (m, 2H), 7.52-7.39(m, 9H), 7.11 (m, 1H), 7.07-7.04 (m, 2H), 6.54 (d, J=15.6, Hz, 1H),5.94-5.78 (m, 2H), 5.67 (t, J=10.9 Hz, 1H), 5.64 (s, 1H), 5.54 (dd,J=11.0, 8.2 Hz, 1H), 4.80 (m, 1H), 4.28 (dd, J=11.3, 4.6 Hz, 1H), 4.18(m, 1H), 4.11 (dd, J=9.8, 3.9 Hz, 1H), 3.94 (s, 3H), 3.81 (m, 2H), 3.71(m, 1H), 3.66 (m, 1H), 3.12 (m, 1H), 2.87 (m, 1H), 2.66 (m, 1H), 2.47(m, 1H), 2.34 (m, 1H), 2.19 (m, 1H), 1.90-1.73 (m, 3H), 1.67-1.51 (m,2H), 1.45 (d, J=7.0 Hz, 3H), 1.23 (d, J=6.6 Hz, 3H), 1.22 (d, J=6.8 Hz,3H), 1.16-1.05 (m, 30H), 0.96 (d, J=6.7 Hz, 3H), 0.36-0.26 (m, 18H); ¹³CNMR (75 MHz, CDCl₃) δ 200.4, 159.6, 147.2, 144.2, 134.1, 133.0, 131.9,130.9, 128.5, 127.8, 127.6, 127.1, 126.7, 113.3, 100.6, 86.6, 82.7,79.8, 72.7, 72.1, 66.3, 64.9, 55.0, 46.8, 42.3, 41.5, 37.9, 35.3, 32.0,31.7, 30.8, 26.1, 25.9, 19.5, 18.3, 18.0, 17.9, 14.7, 13.1, 12.3, 10.4,−3.0, −3.7, −3.9, −4.3, −4.4; LRMS (ESI) 1195.7 [M+Na]⁺, 1051.8; HRMS(ESI) calcd for C₇₁H₁₀₈O₈Si₃Na 1195.7250 [M+Na]⁺ found 1195.7297; [α]²⁰_(D) +9.1 (c 1.2, CHCl₃).

(2R,8S,9R,10S,11Z,13S,15S,16R,17E)-9,13,15-tris(tert-Butyldimethylsilyloxy)-2-((4S,5S)-2-(4-methoxyphenyl)-5-methyl-1,3-dioxan-4-yl)-8,10,16-trimethyl-19-trityloxynonadeca-11,17-dien-3-one(70). The procedure for 40 was used with 69 (1.22 g, 1.04 μmol),NiCl₂.6H₂O (0.12 g, 0.52 mmol) and NaBH₄ (0.079 g, 2.08 mmol) to yield70 (0.80 g, 65%) after flash column chromatography (EtOAc/hexane 1:9) asa colorless oil: IR (CHCl₃) 2956, 2929, 2855, 1713, 1615, 1518, 1461,1388, 1251, 1077, 1037, 836, 773 cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ7.70-7.66 (m, 6H), 7.57-7.40 (m, 11H), 7.07-7.04 (m, 2H), 5.92-5.77 (m,2H), 5.65 (m, 1H), 5.64 (s, 1H), 5.52 (m, 1H), 4.78 (m, 1H), 4.30 (dd,J=11.2, 4.6 Hz, 1H), 4.14 (m, 2H), 3.94 (s, 3H), 3.79 (d, J=3.9 Hz, 2H),3.73 (t, J=11.1 Hz, 1H), 3.61 (m, 1H), 2.92-2.79 (m, 2H), 2.72 (t, J=7.4Hz, 2H), 2.65 (m, 1H), 2.22 (m, 1H), 1.91-1.71 (m, 4H), 1.65-1.56 (m,3H), 1.51 (m, 1H), 1.43 (d, J=7.1 Hz, 3H), 1.35 (m, 1H), 1.20 (d, J=6.7Hz, 3H), 1.14-1.12 (m, 21H), 1.08 (d, J=6.2 Hz, 3H), 1.05-1.03 (m, 9H),0.96 (d, J=6.7 Hz, 3H), 0.34-0.25 (m, 18H);

¹³C NMR (75 MHz, CDCl₃) δ 211.5, 159.8, 144.4, 144.3, 134.3, 132.9,132.2, 130.9, 128.6, 127.6, 127.1, 126.8, 113.4, 100.8, 86.7, 83.0,80.1, 72.8, 72.2, 66.4, 65.0, 55.0, 48.2, 42.3, 41.6, 40.6, 38.0, 35.7,33.5, 31.2, 27.6, 26.2, 25.91, 25.87, 23.9, 19.4, 18.4, 18.05, 17.99,14.8, 13.2, 12.0, 9.5, −3.0, −3.6, −3.8, −4.2, −4.3, −4.4; LRMS (ESI)1197.7 [M+Na]⁺, 684.2, 541.1; HRMS (ESI) calcd for C₇₁H₁₁₀O₈Si₃Na1197.7406 [M+Na]⁺, found 1197.7411; [α]²⁰ _(D) +4.6 (c 1.1, CHCl₃).

(2S,3R,8S,9R,10S,11Z,13S,15S,16R,17E)-9,13,15-tris(tert-Butyldimethylsilyloxy)-2-((4S,5S)-2-(4-methoxyphenyl)-5-methyl-1,3-dioxan-4-yl)-8,10,16-trimethyl-19-(trityloxy)nonadeca-11,17-dien-3-ol(71). LiAl(O-t-Bu)₃H (2.0 mL, 1.0 M solution in THF) was added to asolution of 70 (0.80 g, 0.68 mmol) in THF (7 mL). After 30 min ofstirring at room temperature, the reaction was quenched with saturatedaqueous NH₄Cl (1 mL), stirring for 1 h, dried over MgSO₄, filtered,concentrated in vacuo, and chromatographed (EtOAc/hexane 3:17) toprovide the β isomer of 71 (0.76 g, 95%) as a colorless oil: IR (CHCl₃)3538, 2929, 2855, 1615, 1518, 1461, 1385, 1251, 1072, 835, 773, 734cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ 7.70-7.66 (m, 6H), 7.59-7.56 (m, 2H),7.52-7.39 (m, 9H), 7.08-7.05 (m, 2H), 5.93-5.77 (m, 2H), 5.71 (s, 1H),5.67 (t, J=10.2 Hz, 1H), 5.55-5.48 (m, 1H), 4.78 (m, 1H), 4.30 (dd,J=11.4, 4.8 Hz, 1H), 4.15 (m, 1H), 4.09 (m, 1H), 3.94 (s, 3H), 3.88 (dd,J=10.0, 1.5 Hz, 1H), 3.79 (d, J=3.9 Hz, 2H), 3.70 (t, J=11.1 Hz, 1H),3.64 (m, 1H), 3.38 (br, 1H), 2.84 (m, 1H), 2.65 (m, 1H), 2.33 (m, 1H),2.22-1.91 (m, 2H), 1.86-1.71 (m, 3H), 1.66-1.54 (m, 4H), 1.49-1.34 (m,3H), 1.24 (d, J=7.0 Hz, 3H), 1.21 (d, J=6.6 Hz, 3H), 1.15-1.08 (m, 21H),1.09 (d, J=6.9 Hz, 3H), 1.04 (m, 9H), 0.94 (d, J=6.7 Hz, 3H), 0.34-0.25(m, 18H); ¹³C NMR (75 MHz, CDCl₃) δ 160.0, 144.4, 144.3, 134.3, 132.8,132.2, 130.6, 128.6, 127.6, 127.1, 126.7, 113.6, 101.1, 88.9, 86.7,80.1, 76.2, 73.0, 72.2, 66.4, 65.0, 55.1, 42.3, 41.6, 38.2, 37.4, 35.7,35.0, 33.6, 30.3, 28.0, 26.5, 26.1, 25.91, 25.87, 19.5, 18.4, 18.05,17.99, 15.0, 13.2, 11.8, 5.6, −3.0, −3.7, −3.8, −4.2, −4.3; LRMS (ESI)1199.7 [M+Na]⁺, 937.6, 782.4, 413.2; HRMS (ESI) calcd for C₇₁H₁₁₂O₈Si₃Na1199.7563 [M+Na]⁺, found 1199.7538; [α]²⁰ _(D) +8.9 (c 0.46, CHCl₃).

(2S,3R,8S,9R,10S,11Z,13S,15S,16R,17E)-9,13,15-tris(tert-Butyldimethylsilyloxy)-2-((4S,5S)-2-(4-methoxyphenyl)-5-methyl-1,3-dioxan-4-yl)-8,10,16-trimethyl-19-(trityloxy)nonadeca-11,17-dien-3-ol(72). The procedure for 42 was used with 71 (0.76 g, 0.65 μmol), TBSOTf(0.22 mL, 0.98 mmol) and 2,6-lutidine (0.15 mL, 1.30 mmol) to yield 72(0.76 g, 92%) after flash column chromatography (EtOAc/Hexane 1:9) as acolorless oil: IR (CHCl₃) 2955, 2929, 2856, 1615, 1518, 1471, 1388,1251, 1074, 836, 773 cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ 7.60-7.57 (m, 6H),7.52-7.49 (m, 2H), 7.41-7.27 (m, 9H), 6.99-6.96 (m, 2H), 5.83-5.67 (m,2H), 5.56 (t, J=9.2 Hz, 1H), 5.55 (s, 1H), 5.43 (dd, J=10.9, 8.4 Hz,1H), 4.69 (m, 1H), 4.21 (m, 1H), 4.06 (m, 1H), 3.84 (s, 3H), 3.81 (m,1H), 3.76-3.70 (m, 3H), 3.60 (t, J=11.1 Hz, 11H), 3.54 (m, 11H), 2.74 (m11H), 2.54 (m, 1H), 2.14 (m, 11H), 2.00 (t, J=6.7 Hz, 1H), 1.68 (m, 3H),1.58-1.40 (m, 5H), 1.34-1.20 (m, 3H), 1.13 (d, J=6.8 Hz, 3H), 1.10 (m,3H), 1.05-0.95 (m, 42H), 0.84 (d, J=6.4 Hz, 3H), 0.25-0.17 (m, 24H); ¹³CNMR (75 MHz, CDCl₃) δ 159.7, 144.5, 144.3, 134.3, 132.9, 132.4, 131.6,128.7, 127.7, 127.1, 126.8, 113.4, 100.5, 86.7, 81.9, 80.2, 74.7, 73.3,72.3, 66.5, 65.0, 55.1, 42.3, 41.6, 38.9, 38.2, 35.9, 34.0, 33.7, 30.7,28.4, 26.2, 26.0, 25.96, 25.9, 25.7, 19.4, 18.4, 18.1, 14.8, 13.2, 12.3,10.6, −3.0, −3.5, −3.8, −4.2, −4.3; LRMS (ESI) 1313.8 [M+Na]⁺, 782.4,413.2; HRMS (ESI) calcd for C₇₇H₁₂₆O₈Si₄Na 1313.8428 [M+Na]⁺, found1313.8402; [α]²⁰ _(D) +9.5 (c 0.38, CHCl₃).

(2S,3S,4R,5R,10S,11R,12S,13Z,15S,17S,18R,19E)-3-(4-Methoxybenzyloxy)-5,11,15,17-tetrakis(tert-butyldimethylsilyloxy)-2,4,10,12,18-pentamethyl-21-trityloxyhenicosa-13,19-dien-1-ol(73). The procedure for 43 was used with 72 (0.76 g, 0.59 μmol) andDIBAL-H (5.9 mL, 5.9 mmol) to yield 73 (0.69 g, 90%) after flash columnchromatography (EtOAc/Hexane 3:17) as a colorless oil: IR (CHCl₃) 3484,2928, 2856, 1613, 1514, 1471, 1360, 1251, 1037, 835, 773 cm⁻¹; ¹H NMR(300 MHz, CDCl₃) δ 7.62-7.58 (m, 6H), 7.47-7.34 (m, 11H), 7.02-7.00 (m,2H), 5.82-5.68 (m, 2H), 5.55 (t, J=10.0 Hz, 1H), 5.46-5.41 (m, 1H), 4.70(m, 1H), 4.66 (s, 2H), 4.04 (m, 1H), 3.97 (m, 1H), 3.94 (s, 3H), 3.77(m, 1H), 3.70 (d, J=3.3 Hz, 2H), 3.59 (dd, J=6.6, 4.3 Hz, 1H), 3.53 (m,1H), 3.00 (dd, J=5.8, 4.4 Hz, 11H), 2.72 (m 1H), 2.55 (m, 1H), 2.10 (m,1H), 2.02 (m, 1H), 1.77-1.61 (m, 5H), 1.55-1.47 (m, 3H), 1.41-1.33 (m,5H), 1.25 (d, J=7.0 Hz, 3H), 1.14 (d, J=6.9 Hz, 3H), 1.11 (d, J=6.8 Hz,3H), 1.05-0.94 (m, 42H), 0.25-0.16 (m, 24H); ¹³C NMR (75 MHz, CDCl₃) δ159.2, 144.3, 144.2, 134.3, 132.9, 132.2, 130.5, 129.2, 128.6, 127.6,126.8, 113.8, 86.7, 85.6, 80.1, 75.1, 73.4, 72.2, 66.4, 65.0, 55.0,42.3, 41.5, 40.5, 38.2, 37.0, 35.7, 34.7, 33.7, 28.3, 26.2, 25.9, 19.4,18.4, 18.1, 15.7, 14.8, 13.1, 10.1, −3.0, −3.6, −3.8, −3.9, −4.3, −4.4;LRMS (ESI) 1315.8 [M+Na]⁺, 937.6; HRMS (ESI) calcd for C₇₇H₁₂₈O₈Si₄Na1315.8584 [M+Na]⁺, found 1315.8534; [cc]²⁰ _(D) −4.2 (c 1.5, CHCl₃).

((2E,4R,5S,7S,8Z,10S,11R,12S,17R,18R,19S,20S,21Z)-19-(4-Methoxybenzyloxy)-5,7,11,17-tetrakis(tert-butyldimethylsilyloxy)-4,10,12,18,20-pentamethyltetracosa-2,8,21,23-tetraenyloxy)triphenylmethane(74). The procedure for 44 was used with 73 (0.69 g, 0.53 μmol),Dess-Martin reagent (0.34 g, 0.80 mmol) and 1-bromoallyltrimethylsilane(0.66 g, 2.65 mmol), CrCl₂ (0.54 g, 4.39 mmol) and NaH (0.27 g, 10.7mmol) to yield 74 (0.58 g, 82% for 3 steps) after flash columnchromatography (EtOAc/hexane 1:19) as a colorless oil: IR (CHCl₃) 2955,2929, 2856, 1613, 1514, 1471, 1250, 1063, 836, 773 cm⁻¹; ¹H NMR (300MHz, CDCl₃) δ 7.63-7.60 (m, 6H), 7.43-7.31 (m, 11H), 6.99-6.97 (m, 2H),6.74 (ddd, J=16.8, 10.6, 10.5 Hz, 1H), 6.16 (t, J=11.0 Hz, 1H),5.86-5.71 (m, 3H), 5.58 (t, J=9.8 Hz, 1H), 5.46 (dd, J=11.0, 8.3 Hz,1H), 5.31 (d, J=16.8 Hz, 1H), 5.23 (d, J=10.2 Hz, 1H), 4.75-4.63 (m,3H), 4.09 (m, 1H), 3.86 (s, 3H), 3.81 (m, 1H), 3.73 (d, J=4.0 Hz, 1H),3.55 (m, 1H), 3.49 (m, 1H), 3.18 (m, 1H), 2.77 (m, 1H), 2.57 (m, 1H),1.91-1.78 (m, 2H), 1.73-1.50 (m, 6H), 1.49-1.35 (m, 3H), 1.26 (d, J=6.6Hz, 3H), 1.15 (d, J=6.3 Hz, 3H), 1.13 (d, J=5.9 Hz, 3H), 1.10-0.97 (m,42H), 0.28-0.19 (m, 24H); ¹³C NMR (75 MHz, CDCl₃) δ 159.2, 144.5, 144.4,134.6, 134.4, 133.0, 132.5, 132.4, 131.3, 129.1, 129.0, 128.7, 127.7,126.8, 117.2, 113.7, 86.8, 84.3, 80.3, 75.0, 72.6, 72.3, 66.5, 65.1,55.1, 42.4, 41.6, 40.7, 38.0, 36.0, 35.3, 35.2, 34.0, 28.2, 26.3, 26.03,26.00, 25.97, 25.7, 19.4, 18.8, 18.5, 18.2, 18.14, 18.09, 14.8, 13.3,9.4, −2.9, −3.5, −3.6, −3.8, −4.1, −4.2, −4.3, −4.4; LRMS (ESI) 1337.8[M+Na]⁺, 537.4, 243.1; HRMS (ESI) calcd for C₈₀H₁₃₀O₇Si₄Na 1337.8791[M+Na]⁺, found 1337.8785; [α]²⁰ _(D) +5.1 (c 0.37, CHCl₃).

(2E,4R,5S,7S,8Z,105,11R,12S,17R,18R,19S,20S,21Z)-19-(4-Methoxybenzyloxy)-5,7,11,17-tetrakis(tert-butyldimethylsilyloxy)-4,10,12,18,20-pentamethyltetracosa-2,8,21,23-tetraen-1-ol(75). The procedure for 45 was used with 74 (0.58 g, 0.22 μmol), ZnBr(0.25 g, 1.11 mmol) to yield 75 (0.42 g, 89%) after flash columnchromatography (EtOAc/hexane 3:17) as a colorless oil: IR (CHCl₃) 3402,2956, 2929, 2856, 1614, 1514, 1471, 1251, 1085, 836, 773 cm⁻¹′; ¹H NMR(300 MHz, CDCl₃) δ 7.47-7.44 (m, 2H), 7.04-7.01 (m, 2H), 6.76 (ddd,J=16.8, 10.6, 10.5 Hz, 1H), 6.19 (t, J=11.0 Hz, 1H), 5.87-5.72 (m, 3H),5.59 (t, J=10.0 Hz, 1H), 5.45 (dd, J=10.9, 8.3 Hz, 1H), 5.35 (d, J=16.8Hz, 1H), 5.27 (d, J=10.2 Hz, 1H), 4.75-4.65 (m, 3H), 4.22 (d, J=4.5 Hz,2H), 4.09 (m, 1H), 3.94 (s, 3H), 3.83 (m, 1H), 3.56 (m, 1H), 3.51 (m,1H), 3.17 (m, 1H), 2.77 (m, 1H), 2.57 (m, 1H), 1.95 (m, 1H), 1.85 (m,1H), 1.78-1.55 (m, 8H), 1.53-1.40 (m, 3H), 1.29 (d, J=6.7 Hz, 3H),1.56-1.06 (m, 45H), 1.01 (d, J=6.7 Hz, 3H), 0.29-0.22 (m, 24H); ¹³C NMR(75 MHz, CDCl₃) δ 158.9, 134.8, 134.5, 132.8, 132.4, 132.3, 131.2,129.2, 129.1, 128.9, 117.1, 113.6, 84.3, 80.2, 75.0, 72.4, 72.2, 66.5,63.6, 55.1, 42.3, 41.5, 40.5, 37.9, 35.7, 35.2, 33.8, 28.1, 26.2, 25.9,25.6, 19.3, 18.8, 18.4, 18.2, 18.0, 14.6, 13.0, 9.2, −3.0, −3.5, −3.7,−3.9, −4.3, −4.4, −4.5; LRMS (ESI) 1095.7 [M+Na]⁺, 809.6, 677.5, 537.4,413.2; HRMS (ESI) calcd for C₆₁H₁₁₆O₇Si₄Na 1095.7696 [M+Na]⁺, found1095.7712; [α]²⁰ _(D) +4.8 (c 1.7, CHCl₃).

(2Z,4E,6R,7S,9S,10Z,12S,13R,14S,19R,20R,21S,22S,23Z)-Methyl-21-(4-methoxybenzyloxy)-7,9,13,19-tetrakis(tert-butyldimethylsilyloxy)-6,12,14,20,22-pentamethylhexacosa-2,4,10,23,25-pentaenoate(76). The procedure for 46 was used with 75 (0.42 g, 0.39 μmol),Dess-Martin reagent (0.25 g, 0.59 mmol) andbis(2,2,2-trifluoroethyl)-(methoxycarbonylmethyl) phosphate (0.10 mL,0.47 μmol), 18-crown-6 (0.52 g, 1.97 mmol) and KHMDS (0.94 mL, 0.47mmol) to yield 76 (0.38 g, 86% for 2 steps) by flash columnchromatography (EtOAc/hexane 1:19) as a colorless oil: IR (CHCl₃) 2955,2856, 1722, 1640, 1514, 1462, 1250, 1174, 1084, 836, 773 cm⁻¹; ¹H NMR(300 MHz, CDCl₃) δ 7.44 (dd, J=15.3, 11.3 Hz, 1H), 7.31-7.29 (m, 2H),6.90-6.87 (m, 2H), 6.04 (t, J=11.0 Hz, 1H), 6.02 (m, 1H), 5.66-5.60 (m,2H), 5.44 (t, J=10.0 Hz, 1H), 5.30 (dd, J=11.1, 8.3 Hz, 1H), 5.20 (d,J=16.8 Hz, 1H), 5.12 (d, J=10.2 Hz, 1H), 4.61-4.51 (m, 3H), 3.98 (m,1H), 3.80 (s, 3H), 3.73 (s, 3H), 3.68 (m, 1H), 3.42 (m, 1H), 3.37 (dd,J=7.6, 3.1 Hz, 1H), 3.03 (m, 1H), 2.60 (m, 2H), 1.72 (m, 2H), 1.61-1.41(m, 1H), 1.38-1.27 (m, 3H), 1.20-1.15 (m, 2H), 1.14 (d, J=6.7 Hz, 3H),1.08 (d, J=6.8 Hz, 3H), 1.01 (d, J=6.6 Hz, 3H), 1.00 (d, J=6.7 Hz, 3H),0.99-0.87 (m, 39H), 0.16-0.07 (m, 24H); ¹³C NMR (75 MHz, CDCl₃) δ 166.7,159.0, 147.1, 145.4, 134.5, 132.6, 132.3, 131.3, 129.0, 128.9, 126.8,117.1, 115.4, 113.6, 84.3, 80.2, 75.0, 72.5, 72.1, 66.4, 55.1, 50.8,43.4, 42.4, 40.6, 37.9, 35.9, 35.2, 33.9, 28.1, 26.2, 26.0, 25.90,25.87, 25.6, 19.3, 18.8, 18.4, 18.1, 18.05, 18.04, 14.6, 13.3, 9.3,−3.0, −3.5, −3.7, −3.8, −4.2, −4.3, −4.4, −4.5; LRMS (ESI) 1149.7[M+Na]⁺, 995.7, 436.2; HRMS (ESI) calcd for C₆₄H₁₁₈O₈Si₄Na 1149.7802[M+Na]⁺, found 149.7813; [α]²⁰ _(D) −3.8 (c 0.85, CHCl₃).

(2Z,4E,6R,7S,9S,10Z,12S,13R,14S,19R,20R,21S,22S,23Z)-Methyl-7,9,13,19-tetrakis(tert-butyldimethylsilyloxy)-21-hydroxy-6,12,14,20,22-pentamethylhexacosa-2,4,10,23,25-pentaenoate(77). The procedure for 47 was used with 76 (0.38 g, 0.34 μmol) and DDQ(0.084 g, 0.37 mmol) to yield 77 (0.28 g, 82%) after flash columnchromatography (EtOAc/hexane 1:9) as a colorless oil: IR (CHCl₃) 3542,2956, 2856, 1722, 1640, 1462, 1254, 1175, 1086, 1004, 836, 773 cm⁻¹; ¹HNMR (300 MHz, CDCl₃) δ 7.39 (dd, J=15.2, 11.2 Hz, 1H), 6.63 (ddd,J=16.9, 10.5, 10.4 Hz, 1H), 6.53 (t, J=11.3 Hz, 1H), 6.09 (t, J=11.0 Hz,1H), 5.98 (dd, J=8.3, 7.1 Hz, 1H), 5.58 (d, J=11.3 Hz, 1H), 5.45-5.39(m, 2H), 5.26 (dd, J=10.8, 8.4 Hz, 1H), 5.20 (d, J=16.9 Hz, 1H), 5.11(d, J=10.1 Hz, 1H), 4.53 (m, 1H), 3.95 (m, 1H), 3.76 (m, 1H), 3.71 (s,3H), 3.47 (m, 1H), 3.40 (m, 1H), 2.82 (m, 1H), 2.55 (m, 1H), 2.20 (br,1H), 1.72 (m, 2H), 1.60-1.35 (m, 5H), 1.32-1.10 (m, 5H), 1.04 (d, J=6.8Hz, 3H), 0.99-0.83 (m, 48H), 0.12-0.03 (m, 24H); ¹³C NMR (75 MHz, CDCl₃)δ 166.7, 147.1, 145.4, 135.2, 132.6, 132.5, 132.3, 130.0, 126.8, 117.7,115.5, 80.2, 77.3, 76.2, 72.1, 66.5, 50.9, 43.4, 42.5, 38.3, 38.1, 36.1,35.8, 34.7, 33.7, 28.3, 26.2, 25.94, 25.89, 25.5, 19.5, 18.4, 18.1,17.7, 14.9, 13.3, 7.2, −3.0, −3.6, −3.8, −4.18, −4.20, −4.37, −4.41;LRMS (ESI) 1029.7 [M+Na]⁺, 875.6, 379.3; HRMS (ESI) calcd forC₅₆H₁₁₀O₇Si₄Na 1029.7226 [M+Na]⁺, found 1029.7244; [α]²⁰ _(D) −18.7 (c0.62, CHCl₃).

(8S,10S,14R,20R)-tetrakis(tert-Butyldimethylsilyloxy)-(7R,13S,15S,21S)-tetramethyl-(22S)-((1S)-methylpenta-2,4-dienyl)-oxacyclodocosa-3,5,11-trien-2-one(78). The procedure for 48 was used with 77 (0.28 g, 0.28 μmol) and 1NKOH (2.8 mL, 2.8 mmol) to yield the acid (0.27 g, quantitative) as apale yellow oil, which was used directly in next step: IR (CHCl₃) 2930,1693, 1635, 1462, 1387, 1255, 1089, 838, 773 cm⁻¹; ¹H NMR (300 MHz,CDCl₃) δ 7.36 (dd, J=15.0, 11.4 Hz, 1H), 6.6-6.57 (m, 2H), 6.08 (t,J=10.9 Hz, 1H), 6.02 (dd, J=15.7, 7.0 Hz, 1H), 5.59 (d, J=11.3 Hz, 1H),5.45-5.39 (m, 2H), 5.26 (m, 1H), 5.20 (d, J=17.8 Hz, 1H), 5.11 (d,J=10.2 Hz, 1H), 4.55 (m, 1H), 3.95 (m, 1H), 3.76 (m, 1H), 3.49 (m, 1H),3.41 (m, 1H), 2.82 (m, 1H), 2.57 (m, 2H), 1.70 (m, 2H), 1.57-1.41 (m,5H), 1.31-1.12 (m, 5H), 1.04 (d, J=6.7 Hz, 3H), 0.99-0.84 (m, 48H),0.12-0.04 (m, 24H); ¹³C NMR (75 MHz, CDCl₃) δ 170.9, 147.7, 146.8,134.9, 132.5, 132.4, 132.2, 130.0, 126.9, 117.6, 115.5, 80.1, 75.7,72.0, 66.4, 58.1, 43.4, 42.5, 38.3, 38.1, 35.9, 35.6, 34.7, 33.5, 28.3,26.2, 25.90, 25.85, 25.5, 25.1, 19.5, 18.4, 18.1, 18.0, 17.7, 14.9,13.3, 7.3, −3.1, −3.7, −3.8, −3.9, −4.2, −4.3, −4.4, −4.5; LRMS (ESI)1015.7 [M+Na]⁺, 861.6, 729.5, 651.4; HRMS (ESI) calcd for C₅₅H₁₀₈O₇Si₄Na1015.7070 [M+Na]⁺, found 1015.7091; [α]²⁰ _(D) −14.6 (c 1.4, CHCl₃). Theprocedure for 49 was used with the acid (0.26 g, 0.26 μmol),2,4,6-trichlorobenzoyl chloride (0.21 mL, 1.30 mmol), Et₃N (0.22 mL,1.56 mmol) and 4-DMAP (130 mL, 2.6 mmol) to yield 78 (0.19 g, 76% for 2steps) by flash column chromatography (EtOAc/hexane 1:19) as a colorlessoil: IR (CHCl₃) 2956, 2929, 2856, 1714, 1640, 1471, 1255, 1088, 836, 773cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ 7.16 (dd, J=15.6, 11.2 Hz, 1H), 6.61(ddd, J=16.8, 10.6, 10.5 Hz, 1H), 6.52 (t, J=11.3 Hz, 1H), 6.03 (d,J=9.6, 5.9 Hz, 1H), 6.00 (t, J=10.6 Hz, 1H), 5.62 (t, J=10.5 Hz, 1H),5.56 (d, J=11.3 Hz, 1H), 5.39 (t, J=10.5 Hz, 1H), 5.28 (dd, J=11.2, 8.0Hz, 1H), 5.20-5.14 (m, 2H), 5.09 (d, J=10.3 Hz, 1H), 4.59 (m, 1H), 4.01(m, 1H), 3.53 (m, 1H), 3.43 (m, 1H), 3.06 (m, 1H), 2.56 (m, 1H), 2.45(m, 1H), 1.90 (m, 1H), 1.55-1.35 (m, 6H), 1.28 (m, 1H), 1.24-1.12 (m,4H), 1.08 (d, J=6.7 Hz, 3H), 1.02 (d, J=5.9 Hz, 3H), 1.01 (d, J=6.0 Hz,3H), 0.93-0.88 (m, 39H), 0.81 (d, J=6.9 Hz, 3H), 0.14-0.05 (m, 24H); ¹³CNMR (75 MHz, CDCl₃) δ 166.2, 144.1, 142.6, 133.9, 132.1, 131.5, 129.7,128.0, 127.5, 117.8, 117.6, 80.3, 74.0, 71.2, 66.5, 62.4, 43.7, 39.8,39.3, 34.9, 34.0, 33.0, 31.8, 27.8, 26.1, 26.05, 25.98, 20.1, 18.33,18.28, 18.14, 18.11, 17.8, 16.1, 14.0, 10.7, −2.7, −3.8, −4.0, −4.1,−4.2, −4.3; LRMS (ESI) 997.7 [M+Na]⁺, 843.6, 711.5, 579.4; HRMS (ESI)calcd for C₅₅H₁₀₆O₆Si₄Na 997.6964 [M+Na]⁺, found 997.6989; [α]²⁰ _(D)−26.4 (c 0.59, CHCl₃).

(8S,10S,14R,20R)-Tetrahydroxy-(7R,13S,15S,21S)-tetramethyl-(22S)-((1S)-methylpenta-2,4-dienyl)-oxacyclodocosa-3,5,11-trien-2-one(79). The procedure for 1 was used with 78 (0.19 g, 0.19 μmol), 3N HClin 15 ml of 2:1 MeOH/THF to yield 79 (25 mg, 24%) after flash columnchromatography (EtOAc/hexane 3:7) as a colorless oil: IR (CHCl₃) 3414,2965, 2930, 1708, 1637, 1454, 1375, 1273, 1182, 1046, 968 cm⁻¹; H HNMR(600 MHz, CD₃OD) δ 7.22 (dd, J=15.4, 11.2 Hz, 1H), 6.67 (ddd, J=17.3,11.0, 10.5 Hz, 1H), 6.64 (dd, J=11.4, 11.4 Hz, 1H), 6.07 (dd, J=15.4,7.7 Hz, 1H), 6.02 (dd, J=10.9, 10.9 Hz, 1H), 5.55 (t, J=10.6 Hz, 1H),5.52 (d, J=11.4 Hz, 1H), 5.43 (dd, J=10.9, 9.0 Hz, 1H), 5.35 (dd,J=10.7, 10.6 Hz, 1H), 5.20 (d, J=16.7 Hz, 1H), 5.12 (d, J=10.2 Hz, 1H),5.08 (dd, J=5.9, 5.9 Hz, 1H), 4.64 (m, 1H), 3.86 (ddd, J=8.4, 4.7, 4.5Hz, 1H), 3.43 (m, 1H), 3.16 (m, 1H), 3.14 (dd, J=8.1, 2.6 Hz, 1H), 2.73(m, 1H), 2.37 (m, 1H), 1.84 (m, 1H), 1.68 (m, 1H), 1.51-1.45 (m, 3H),1.31 (m, 1H), 1.20 (m, 1H), 1.14-1.11 (m, 1H), 1.08 (d, J=6.9 Hz, 6H),1.07-1.01 (m, 2H), 0.99 (d, J=6.8 Hz, 3H), 0.98 (d, J=6.7 Hz, 3H), 0.95(m, 1H), 0.92 (d, J=6.6 Hz, 3H); ¹³C NMR (150 MHz, CD₃OD) δ 168.2,146.6, 144.8, 134.3, 133.8, 133.4, 132.2, 131.3, 129.1, 118.5, 118.0,79.9, 79.3, 72.4, 71.0, 65.5, 44.9, 41.7, 40.7, 37.9, 36.0, 35.4, 35.2,33.9, 27.4, 27.2, 19.5, 18.3, 16.4, 15.1, 10.1; LRMS (ESI) 541.3[M+Na]⁺, 483.3; HRMS (ESI) calcd for C₃₁H₅₀O₆Na 541.3505 [M+Na]⁺, found541.3521; [α]²⁰ _(D) −34.4 (c 0.18, MeOH).

(3S,4SE)-3-(tert-Butyldimethylsilyloxy)-N-methoxy-N,4-dimethyl-7-(trityloxy)hept-5-enamide(81).(3S,4S,E)-3-(tert-Butyldimethylsilyloxy)-4-methyl-7-trityloxyhept-5-en-1-ol(0.34 g, 0.66 mmol) in CH₂Cl₂ (10 mL) was treated with Dess-Martinperiodinane (0.41 g, 0.99 mmol). After 1 h, the mixture was quenchedwith saturated NaHCO₃ (10 mL). The aqueous layer was extracted withethyl ether (10 mL×2) and the combined extracts were dried overanhydrous MgSO₄. Filtration and concentration followed by short flashcolumn chromatography (hexane/EtOAc 8:2) to remove the Dess-Martinresidue provided the aldehyde as a colorless oil, which was used for thenext reaction without further purification. A solution of the abovealdehyde in THF (10 mL) and H₂O (5 mL) was treated with a 2 M solutionof 2-methyl-2-butene (1.9 mL, 0.95 mmol) in THF, NaH₂PO₄—H₂O (0.27 g,1.96 mmol) and NaClO₂ (0.22 g, 1.96 mmol). The reaction mixture wasstirred for 2 h, diluted with 1N HCl (20 mL) and extracted with CH₂Cl₂(2×40 mL). The combined organic layers were dried over MgSO₄,concentrated in vacuo and the crude was used for the next reactionwithout further purification. To a solution of acid in CH₂Cl₂, N,O-dimethylhydroxylamine hydrochloride (0.064 g, 0.65 mmol), Et₃N (0.09mL, 0.65 mmol), DMAP (8 mg, 0.065 mmol) were successively added. Thereaction mixture was cooled to 0° C., DCC (0.14 g, 0.65 mmol) was added.The mixture was stirred at ambient temperature for 15 h and filtered.The filtrate was washed with 0.5 N HCl, saturated aqueous NaHCO₃, andbrine, dried over anhydrous MgSO₄ and concentrated. Purification bycolumn chromatography over silica gel (hexane/EtOAc 4:1) gave theWeinreb amide 81 (0.37 g, 81% for 3 steps) as a colorless oil: IR(CHCl₃) 2956, 2929, 2855, 1661, 1448, 1385, 1251, 1089, 1054, 1003, 836,775, 706 cm⁻¹; ¹H NMR (300 MHz, CDCl₃)

7.64-7.61 m, 6H), 7.45-7.33 (m, 9H), 6.09 (dd, J=15.7, 6.6 Hz, 1H), 5.75(dt, J=15.7, 5.2 Hz, 1H), 4.42 (m, 1H), 3.76 (s, 3H), 3.70 (m, 2H), 3.29(s, 3H), 2.88 (m, 1H), 2.55 (m, 2H), 1.18 (d, J=6.8 Hz, 3H), 1.06 (s,9H), 0.27 (s, 3H), 0.20 (s, 3H); ¹³C NMR (75 MHz, CDCl₃) δ 172.5, 144.2,133.5, 128.5, 127.6, 126.8, 86.5, 72.8, 64.6, 61.1, 42.2, 36.0, 31.9,25.8, 18.0, 14.8, −4.7, −4.8; LRMS (EI) 573, 558, 516, 246, 165; HRMS(EI) calcd for C₃₅H₄₇O₄N₁Si₁ 573.3290, found 573.3290; [α]²⁰ _(D) −40.1(c 1.2, CHCl₃).

(4S,5S,10S,11R,12R,14R,E)-11-(4-Methoxybenzyloxy)-5,15-bis(tert-butyldimethylsilyloxy)-4,10,12,14-tetramethyl-1-(trityloxy)pentadec-2-en-8-yn-7-one (82). Alkyne80 (7.75 g, 18.5 mmol) was taken up in THF (185 mL) and cooled to −78°C. n-BuLi (11.6 mL, 1.6 M solution in hexane) was added slowly. After 5min, the mixture was warmed to 0° C. and stirred for 30 min. The mixturewas then cooled to −78° C. and amide 81 (5.31 g, 9.26 mmol) in THF (15mL) was added slowly. After 5 min the solution was warmed to 0° C. andstirred for 1 h. The reaction was quenched with aq NH₄Cl and the mixturewas partitioned in a separatory funnel. The aqueous phase was extractedwith ether (50 mL×3) and combined organic extracts were washed withbrine and dried over MgSO₄. Filtration and concentration under reducedpressure, followed by flash chromatography on silica gel (hexane/EtOAc95:5) afforded ynone (8.45 g, 98%) as a pale yellow oil: IR (CHCl₃)2955, 2929, 2856, 2208, 1674, 1514, 1470, 1249, 1092, 836, 775, 706cm⁻¹; ¹H NMR (300 MHz, CDCl₃)

7.50-7.47 m, 6H), 7.35-7.22 (m, 11H), 6.88-6.84 (m, 2H), 5.81 (dd,J=15.6, 6.7 Hz, 1H), 5.58 (dt, J=15.6, 5.2 Hz, 1H), 4.64 (d, J=10.8 Hz,1H), 4.54 (d, J=10.8 Hz, 1H), 4.27 (m, 1H), 3.80 (s, 3H), 3.59 (d, J=5.2Hz, 2H), 3.44-3.34 (m, 2H), 3.18 (t, J=5.4 Hz, 1H), 2.94 (m, 1H), 2.62(m, 1H), 2.38 (m, 1H), 1.89 (m, 1H), 1.68 (m, 1H), 1.26 (d, J=7.0 Hz,3H), 1.24 (m, 1H), 0.99 (d, J=6.9 Hz, 3H), 0.97 (d, J=6.9 Hz, 3H), 0.92(s, 9H), 0.91 (m, 1H), 0.89 (s, 9H), 0.84 (d, J=6.7 Hz, 3H), 0.09-0.05(m, 12H); ¹³C NMR (75 MHz, CDCl₃) δ 186.4, 159.1, 144.3, 133.5, 130.7,129.2, 128.7, 127.7, 127.3, 126.9, 113.7, 96.8, 86.8, 86.2, 82.6, 74.0,72.3, 69.2, 64.9, 55.2, 50.5, 42.3, 34.9, 33.2, 33.0, 29.5, 26.0, 25.9,18.3, 18.1, 17.2, 16.3, 15.9, 14.8, −4.50, −4.55, −5.3; LRMS (ESI) 953.6[M+Na]+, 855.4, 797.4, 577.5, 413.4, 359.3, 328.4; HRMS (ESI) calcd forC₅₈H₈₂O₆Si₂Na 953.5548 [M+Na]+, found 953.5552; [α]²⁰ _(D) −9.5 (c 2.8,CHCl₃).

(4S,5S,7S,10S,11R,12R,14R,E)-11-(4-Methoxybenzyloxy)-5,15-bis(tert-butyldimethylsilyloxy)-4,10,12,14-tetramethyl-1-(trityloxy)pentadec-2-en-8-yn-7-ol(83). Ynone 82 (7.06 g, 7.59 mmol) was taken up in i-PrOH (100 mL).Noyori catalyst (1.02 g, 1.52 mmol, 20 mol %) was added in one portionand the solution was stirred for 12 h. The solvent was removed undervacuum, and the crude residue was purified by flash chromatography onsilica gel (hexane/EtOAc 9:1), affording propargylic alcohol 83 (6.16 g,87%) as a pale yellow oil: IR (CHCl₃) 3434, 2955, 2928, 2855, 1613,1513, 1462, 1250, 1091, 836, 775 cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ7.59-7.57 (m, 6H), 7.42-7.30 (m, 11H), 6.96-6.93 (m, 2H), 5.96 (dd,J=15.7, 6.4 Hz, 1H), 5.68 (dt, J=15.2, 5.3 Hz, 1H), 4.79 (d, J=10.8 Hz,1H), 4.67 (m, 1H), 4.63 (d, J=10.9 Hz, 1H), 4.07 (m, 1H), 3.86 (s, 3H),3.69 (d, J=4.7 Hz, 2H), 3.49 (m, 2H), 3.22 (t, J=5.5 Hz, 1H), 2.91 (m,1H), 2.67 (d, J=5.3 Hz, 1H), 2.56 (m, 1H), 1.98 (m, 1H), 1.86 (m, 2H),1.77 (m, 1H), 1.36 (m, 1H), 1.31 (d, J=7.0 Hz, 3H), 1.09 (d, J=7.1 Hz,3H), 1.06 (d, J=7.1 Hz, 3H), 1.03 (s, 9H), 1.02 (s, 9H), 0.94 (d, J=6.6Hz, 3H), 0.24 (s, 3H), 0.22 (s, 3H), 0.15 (s, 6H); ¹³C NMR (75 MHz,CDCl₃) δ 158.9, 144.3, 133.2, 131.0, 129.1, 128.6, 127.7, 127.0, 126.8,113.5, 87.5, 86.79, 86.74, 82.6, 74.0, 73.3, 69.3, 65.0, 59.6, 55.1,41.4, 40.2, 34.5, 33.1, 32.7, 29.1, 25.9, 18.3, 18.0, 17.9, 16.6, 15.8,15.3, −4.3, −4.5, −5.4; LRMS (ESI) 955.6 [M+Na]+, 707.3, 633.3, 559.2,413.3; HRMS (ESI) calcd for C₅₈H₈₄O₆Si₂Na 955.5704 [M+Na]+, found955.5734; [α]²⁰ _(D) −8.5 (c 1.5, CHCl₃).

(2E,4S,5S,7S,8Z,10S,11R,12R,14R)-11-(4-Methoxybenzyloxy)-5-(tert-butyldimethylsilyloxy)-15-(tert-butyldimethylsilyloxy))-4,10,12,14-tetramethyl-1-(trityloxy)pentadeca-2,8-dien-7-ol(84). A catalytic amount of Lindlar catalyst (ca. 200 mg) was added to asolution of alcohol 83 (3.11 g, 3.33 mmol) in toluene (100 mL). Theflask was fitted with a H₂ balloon, and stirred under an atmosphere ofH₂ until starting material was consumed (usually 1 h), as indicated byTLC analysis. The mixture was filtered through a pad of celite andconcentrated under reduced pressure to afford the olefin 84 as acolorless oil (2.81 g, 90%): IR (CHCl₃) 3434, 2956, 2928, 2856, 1613,1514, 1471, 1249, 1062, 836, 774 cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ7.58-7.55 (m, 6H), 7.4-7.29 (m, 1H), 6.93 (m, 2H), 5.90 (dd, J=15.6, 6.6Hz, 1H), 5.68 (dt, J=15.7, 5.4 Hz, 1H), 5.60 (dd, J=11.1, 8.9 Hz, 1H),5.51 (dd, J=11.2, 7.3 Hz, 1H), 4.66 (m, 1H), 4.58 (d, J=10.9 Hz, 1H),4.55 (d, J=10.9 Hz, 1H), 3.95 (m, 1H), 3.86 (s, 3H), 3.66 (dd, J=4.9 Hz,1H), 3.52-3.38 (m, 2H), 3.01 (m, 2H), 2.89 (br, 1H), 2.55 (m, 1H), 1.79(m, 1H), 1.70 (m, 1H), 1.62 (m, 2H), 1.33-1.29 (m, 2H), 1.12 (d, J=5.8Hz, 3H), 1.10 (d, J=6.7 Hz, 3H), 1.02 (s, 9H), 1.01 (s, 9H), 0.89 (d,J=6.1 Hz, 3H), 0.87 (d, J=6.3 Hz, 3H), 0.19 (s, 6H), 0.14 (s, 6H); ¹³CNMR (75 MHz, CDCl₃) δ 158.9, 144.3, 134.1, 133.5, 132.6, 131.0, 129.0,128.6, 127.7, 126.8, 126.7, 113.5, 88.4, 86.7, 74.9, 73.5, 69.4, 65.2,65.1, 55.1, 41.8, 40.2, 35.0, 34.6, 33.1, 25.9, 19.1, 18.3, 18.0, 16.6,15.8, 15.6, −4.4, −4.5, −5.3; LRMS (ESI) 957.6 [M+Na]+, 781.4, 707.3,559.3, 485.2, 413.4; HRMS (ESI) calcd for C₅₈H₈₆O₆Si₂Na 957.5861[M+Na]+, found 957.5900; [α]²⁰ _(D) +2.0 (c 1.2, CHCl₃).

((2E,4S,5S,7S,8Z,10S,11R,12R,14R)-11-(4-Methoxybenzyloxy)-5,7,15-tris(tert-butyldimethylsilyloxy)-4,10,12,14-tetramethylpentadeca-2,8-dienyloxy)triphenylmethane(85). TBSOTf (1.05 mL, 4.57 mmol) was added to a stirred solution of thealcohol 84 (3.89 g, 4.16 mmol) and 2,6-lutidine (0.58 mL, 5.01 mmol) inCH₂Cl₂ (14 mL) at 0° C. After stirring for 1 h at 0° C., the reactionmixture was quenched by the addition of water (25 mL), and extracted byCH₂Cl₂ and dried over MgSO₄, followed by the evaporation of the solventunder reduced pressure. The residue was purified by short columnchromatography (hexane/EtOAc 9:1) to obtain the product 85 (4.36 g,quantitative) as a colorless oil: IR (CHCl₃) 2956, 2928, 2856, 1613,1514, 1471, 1462, 1250, 1088, 836, 773, 705 cm⁻¹; ¹H NMR (300 MHz,CDCl₃) δ 7.61-7.58 (m, 6H), 7.43-7.31 (m, 11H), 6.97-6.94 (m, 2H), 5.95(dd, J=15.7, 6.0 Hz, 1H), 5.67 (dt, J=15.7, 5.6 Hz, 1H), 5.62-5.46 (m,2H), 4.71 (m, 1H), 4.62 (m, 2H), 4.05 (m, 1H), 3.87 (s, 3H), 3.69 (d,J=5.3 Hz, 2H), 3.53-3.40 (m, 2H), 3.08 (m, 1H), 2.91 (m, 1H), 2.51 (m,1H), 1.76 (m, 1H), 1.66 (m, 2H), 1.50-1.40 (m, 2H), 1.32 (m, 1H), 1.22(d, J=6.8 Hz, 6H), 1.09 (d, J=6.9 Hz, 3H), 1.06-0.96 (m, 27H), 0.91 (d,J=6.6 Hz, 3H), 0.83 (d, J=6.5 Hz, 3H), 0.25-0.17 (m, 18H); ¹³C NMR (75MHz, CDCl₃) δ 158.9, 144.4, 134.3, 133.7, 131.4, 129.4, 129.0, 128.6,127.7, 126.8, 126.4, 113.5, 88.8, 86.7, 74.8, 72.8, 69.5, 66.3, 65.1,55.1, 43.0, 42.3, 35.4, 35.1, 33.4, 33.1, 26.1, 26.0, 18.8, 18.3, 18.1,16.7, 15.7, 14.6, −2.8, −3.9, −4.1, −4.2, −5.3; LRMS (ESI) 1071.9[M+Na]+, 413.4, 359.3, 243.2; HRMS (ESI) calcd for C₆₄H₁₀₀O₆Si₃Na1071.6725 [M+Na]+, found 1071.6779; [α]²⁰ _(D) −9.5 (c 3.0, CHCl₃).

(2R,4R,5R,6S,7Z,9S,11S,12S,13E)-1,9,11-tris(tert-Butyldimethylsilyloxy)-2,4,6,12-tetramethyl-15-(trityloxy)pentadeca-7,13-dien-5-ol(86). The above PMB alcohol 85 (2.90 g, 2.77 mmol) was added to CH₂Cl₂(25 mL) and H₂O (1 mL), and DDQ (0.94 g, 4.15 μmol) was added. After 1 hof stirring, the reaction mixture was quenched by adding sat'd NaHCO₃(200 mL). The organic phase was washed by sat'd NaHCO₃ solution (3×100mL) and brine, dried over MgSO₄ and concentrated. Purification by flashcolumn chromatography (EtOAc/hexane 5:95) furnished 86 (2.16 g, 84%) asa colorless oil: IR (CHCl₃) 3477, 2956, 2928, 2856, 1471, 1386, 1254,1088, 836, 774 cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ 7.55-7.52 (m, 6H),7.38-7.25 (m, 9H), 5.92 (dd, J=15.7, 6.0 Hz, 1H), 5.62 (dt, J=15.7, 5.5Hz, 1H), 5.52 (dd, J=11.1, 9.3 Hz, 1H), 5.35 (t, J=10.5 Hz, 1H), 4.63(m, 1H), 3.97 (m, 1H), 3.63 (d, J=5.4 Hz, 2H), 3.51-3.36 (m, 2H), 3.18(m, 1H), 2.68 (m, 1H), 2.47 (m, 1H), 1.71-1.59 (m, 3H), 1.42-1.27 (m,2H), 1.17 (m, 1H), 1.08 (d, J=6.7 Hz, 3H), 1.04 (d, J=6.9 Hz, 3H), 0.99(s, 9H), 0.97 (s, 9H), 0.96 (s, 9H), 0.91 (d, J=6.8 Hz, 3H), 0.84 (d,J=6.6 Hz, 3H), 0.18 (s, 3H), 0.16 (s, 3H), 0.15 (s, 3H), 0.13 (s, 3H),0.12 (s, 6H); ¹³C NMR (75 MHz, CDCl₃) δ 144.4, 135.2, 134.1, 131.1,128.7, 127.7, 126.8, 126.4, 86.7, 79.8, 72.8, 69.6, 66.2, 65.2, 43.0,42.1, 35.5, 33.7, 32.8, 32.5, 26.1, 26.0, 25.9, 18.4, 18.1, 17.6, 16.8,16.3, 14.7, −2.9, −4.0, −4.15, −4.22, −5.3; LRMS (ESI) 951.7 [M+Na]+,823.7, 577.4, 413.3, 328.4, 243.1; HRMS (ESI) calcd for C₅₆H₉₂O₅Si₃Na951.6150 [M+Na]+, found 951.6165; [α]²⁰D 30.0 (c 3.6, CHCl₃).

((2E,4S,5S,7S,8Z,10S,11R,12R,14R)-5,7,11,15-tetrakis(tert-Butyldimethylsilyloxy)-4,10,12,14-tetramethylpentadeca-2,8-dienyloxy)triphenylmethane(87). The procedure for 85 was used with above 86 (3.34 g, 3.60 μmol),TBSOTf (1.82 mL, 7.9 mmol) to yield 3.53 g (94%) of the product by flashcolumn chromatography (EtOAc/Hexane 5:95) as a colorless oil: IR (CHCl₃)2956, 2928, 2856, 1471, 1462, 1361, 1254, 1088, 836, 773, 705 cm⁻¹; ¹HNMR (300 MHz, CDCl₃) δ 7.50-7.48 (m, 6H), 7.34-7.22 (m, 9H), 5.82 (dd,J=15.7, 6.0 Hz, 1H), 5.57 (dt, J=15.8, 5.9 Hz, 1H), 5.48 (dd, J=11.0,9.9 Hz, 1H), 5.32 (dd, J=11.0, 8.7 Hz, 1H), 4.56 (m, 1H), 3.93 (m, 1H),3.59 (d, J=5.5 Hz, 2H), 3.39 (dd, J=9.6, 5.8 Hz, 1H), 3.31-3.27 (m, 2H),2.62 (m, 1H), 2.40 (m, 1H), 1.58-1.50 (m, 3H), 1.35 (m, 1H), 1.20-1.09(m, 2H), 1.02 (d, J=7.1 Hz, 3H), 1.00 (d, J=7.0 Hz, 3H), 0.94 (s, 9H),0.92 (s, 9H), 0.91 (s, 9H), 0.90 (s, 9H), 0.78 (d, J=6.8 Hz, 3H), 0.74(d, J=6.6 Hz, 3H), 0.13-0.05 (m, 24H); ¹³C NMR (75 MHz, CDCl₃) δ 144.4,134.5, 133.0, 131.8, 128.7, 127.7, 126.8, 126.4, 86.7, 81.2, 72.8, 69.3,66.6, 65.3, 43.1, 42.3, 35.9, 35.1, 33.3, 29.7, 26.2, 26.1, 26.0, 19.6,18.4, 18.3, 18.2, 16.3, 16.0, 14.6, −2.8, −3.5, −3.6, −4.0, −4.1, −5.3;LRMS (ESI) 1065.7 [M+Na]⁺, 953.7, 615.1, 577.3, 359.2; HRMS (ESI) calcdfor C₆₂H₁₀₆O₅Si₄Na 1065.7015 [M+Na]⁺, found 1065.7068; [α]²⁰ _(D) −22.5(c 2.0, CHCl₃).

(2R,4R,5R,6S,7Z,9S,11S,12S,13E)-5,9,11-tris(tert-Butyldimethylsilyloxy)-2,4,6,12-tetramethyl-15-(trityloxy)pentadeca-7,13-dien-1-ol(88). HF-pyridine in pyridine (40 mL, prepared by slow addition of 12 mLpyridine to 3 mL HF-pyridine complex followed by dilution with 25 mLTHF) was slowly added to a solution of TBS ether 87 (3.54 g, 4.10 mmol)in THF (5 mL) at 0° C. The mixture was stirred for 2 days at 0° C. andquenched with sat'd NaHCO₃ (100 mL). The aqueous layer was separated andextracted with Et₂O (3×50 mL). The combined organic layers were washedwith sat'd CuSO₄ (3×50 mL), dried over MgSO₄, and concentrated. Flashcolumn chromatography (EtOAc/hexane 15:85) afforded 2.08 g (66%) of thealcohol as a colorless oil: IR (CHCl₃) 3400, 2956, 2928, 2856, 1471,1448, 1254, 1075, 836, 773 cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ 7.52-7.48 (m,6H), 7.36-7.24 (m, 9H), 5.87 (dd, J=15.7, 5.9 Hz, 1H), 5.59 (dt, J=15.7,5.7 Hz, 1H), 5.55 (dd, J=10.6, 10.4 Hz, 1H), 5.33 (dd, J=11.0, 8.7 Hz,1H), 4.58 (m, 1H), 3.94 (m, 1H), 3.60 (d, J=5.5 Hz, 2H), 3.38-3.32 (m,2H), 3.25 (m, 1H), 2.62 (m, 1H), 2.45 (m, 1H), 1.59 (m, 1H), 1.55 (m,1H), 1.47 (m, 1H), 1.35 (m, 1H), 1.09 (m, 1H), 1.04 (d, J=7.6 Hz, 3H),1.01 (d, J=7.2 Hz, 3H), 0.96 (s, 9H), 0.94 (s, 9H), 0.93 (s, 9H), 0.79(d, J=6.8 Hz, 3H), 0.75 (d, J=6.6 Hz, 3H), 0.15 (s, 9H), 0.14 (s, 3H),0.10 (s, 3H), 0.09 (s, 3H), 0.08 (s, 3H), 0.07 (s, 3H); ¹³C NMR (75 MHz,CDCl₃) δ 144.4, 134.0, 132.7, 131.3, 128.7, 127.7, 126.8, 126.5, 86.8,81.0, 73.0, 69.2, 66.5, 65.3, 42.6, 42.2, 36.2, 35.5, 34.6, 33.3, 26.2,26.1, 25.9, 20.0, 18.4, 18.2, 18.1, 15.7, 15.6, 14.9, −2.8, −3.7, −3.8,−4.0, −4.1, −4.2; LRMS (ESI) 951.6 [M+Na]+, 705.1, 631.1, 557.0, 397.2,381.2, 353.2, 243.1; HRMS (ESI) calcd for C₅₆H₉₂O₅Si₃Na 951.6150[M+Na]+, found 951.6158; [α]²⁰ _(D) −330.5 (c 2.0, CHCl₃).

(2R,4E,6R,8R,9R,10S,11Z,13S,15S,16S,17E)-9,13,15-tris(tert-Butyldimethylsilyloxy)-2-((4S,5S)-2-(4-methoxy)phenyl)-5-methyl-1,3-dioxan-4-yl)-6,8,10,16-tetramethyl-19-(trityloxy)nonadeca-4,11,17-trien-3-one(89). The alcohol 88 (2.04 g, 2.20 μmol) in CH₂Cl₂ (30 mL) was treatedwith Dess-Martin periodinane (1.40 g, 3.30 μmol). After 1 h, the mixturewas quenched with saturated NaHCO₃ (30 mL) and Na₂S₂O₃ (30 mL). Theaqueous layer was extracted with ethyl ether (30 mL×2) and the combinedextracts were dried over anhydrous MgSO₄. Filtration and concentrationfollowed by short flash column chromatography filtration (hexane/EtOAc4:1) to remove the residue from the Dess-Martin reagent provided crudealdehyde as a colorless oil, which was used for the next reactionwithout further purification. A mixture of ketophosphonate 38 (0.85 g,2.20 mmol) and Ba(OH)₂ (0.30 g, activated by heating to 100° C. for 1-2h before use) in THF (40 mL) was stirred at room temperature for 30 min.A solution of the above aldehyde in wet THF (4 mL+4×1 mL washings, 40:1THF/H₂O) was then added. After stirring for 12 h, the reaction mixturewas diluted with Et₂O (30 mL) and washed with sat'd NaHCO₃ (50 mL) andbrine (50 mL). The organic solution was dried (MgSO₄) and the solventwas evaporated in vacuo. The residue was chromatographed (hexane/EtOAc9:1) to yield 89 (2.04 g, 78% for 2 steps) as a colorless oil: IR(CHCl₃) 2957, 2929, 2855, 1618, 1518, 1461, 1388, 1251, 1078, 1036, 836,773 cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ 7.49-7.46 (m, 6H), 7.39 (m, 2H),7.33-7.21 (m, 9H), 6.89 (m, 2H), 6.79 (dd, J=15.7, 7.4 Hz, 1H), 6.20 (d,J=15.6 Hz, 1H), 5.85 (dd, J=15.7, 5.9 Hz, 1H), 5.58 (dt, J=15.7, 4.6 Hz,1H), 5.49 (dd, J=11.0, 10.4 Hz, 1H), 5.46 (s, 1H), 5.34 (dd, J=11.1, 8.6Hz, 1H), 4.56 (m, 1H), 4.12 (dd, J=11.3, 4.6 Hz, 1H), 3.92 (m, 2H), 3.81(s, 3H), 3.57 (d, J=5.6 Hz, 1H), 3.54 (m, 1H), 3.29 (dd, J=5.6, 2.4 Hz,1H), 2.93 (m, 1H), 2.61 (m, 1H), 2.43 (m, 1H), 2.18 (m, 1H), 2.01 (m,1H), 1.59-1.46 (m, 2H), 1.43 (m, 1H), 1.35-1.29 (m, 2H), 1.25 (d, J=7.0Hz, 3H), 1.03 (d, J=7.2 Hz, 3H), 1.00 (d, J=7.0 Hz, 3H), 0.94 (s, 9H),0.92 (s, 9H), 0.91 (s, 9H), 0.82 (d, J=7.0 Hz, 3H), 0.79 (d, J=6.7 Hz,3H), 0.77 (d, J=6.5 Hz, 3H), 0.13 (s, 3H), 0.12 (s, 3H), 0.09 (s, 3H),0.08 (s, 3H), 0.05 (s, 3H), 0.02 (s, 3H); ¹³C NMR (75 MHz, CDCl₃) δ200.7, 159.8, 153.3, 144.3, 134.0, 133.3, 131.1, 130.8, 128.6, 127.7,127.2, 126.8, 126.5, 125.7, 113.4, 100.8, 86.7, 82.7, 80.4, 72.8, 66.5,65.8, 65.2, 55.2, 47.0, 42.8, 42.1, 39.1, 35.6, 34.9, 34.0, 32.3, 26.1,26.0, 25.9, 19.7, 18.39, 18.36, 18.1, 16.4, 15.2, 14.7, 12.4, 10.7,−2.8, −3.6, −3.7, −4.0, −4.1; LRMS (ESI) 1209.7 [M+Na]+, 577.4, 359.2,243.1, 165.0; HRMS (ESI) calcd for C₇₂H₁₁₀O₈Si₃Na 1209.7406 [M+Na]+,found 1209.7466; [α]²⁰ _(D) −8.6 (c 2.5, CHCl₃).

(2R,6S,8R,9R,10S,11Z,13S,15S,16S,17E)-9,13,15-tris(tert-Butyldimethylsilyloxy)-2-((45,55)-2-(4-methoxyphenyl)-5-methyl-1,3-dioxan-4-yl)-6,8,10,16-tetramethyl-19-(trityloxy)nonadeca-11,17-dien-3-one(90). NiCl₂.6H₂O (0.20 g, 0.84 mmol) then portionwise NaBH₄ (0.17 g,4.49 mmol) were added to a stirred solution of unsaturated ketone 89(2.60 g, 1.72 μmol) in MeOH (60 mL), THF (20 mL) at 0° C. After 1 h, thereaction mixture was evaporated and filtered with celite using Et₂O asan eluent (30 mL). The organic phase was concentrated and the residuewas purified by flash chromatography (EtOAc/hexane 1:9) to yield 90(1.55 g, 76%) as a colorless oil: IR (CHCl₃) 2956, 2929, 2855, 1713,1616, 1518, 1462, 1251, 1076, 836, 773 cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ7.52-7.50 (m, 6H), 7.42-7.24 (m, 11H), 6.92-6.86 (m, 2H), 5.87 (dd,J=15.7, 6.0 Hz, 2H), 5.60 (dt, J=15.8, 5.9 Hz, 1H), 5.50 (m, 1H), 5.49(s, 1H), 5.37 (dd, J=10.9, 8.5 Hz, 1H), 4.59 (m, 1H), 4.17 (dd, J=11.3,4.7 Hz, 1H), 3.98 (m, 2H), 3.82 (s, 3H), 3.62-3.55 (m, 3H), 3.29 (m,1H), 2.73 (m, 1H), 2.65 (m, 1H), 2.49 (m, 2H), 2.06 (m, 1H), 1.63-1.50(m, 2H), 1.47-1.32 (m, 2H), 1.27 (d, J=7.1 Hz, 3H), 1.26 (m, 1H), 1.06(d, J=7.3 Hz, 3H), 1.03 (d, J=7.2 Hz, 3H), 0.97-0.94 (m, 27H), 0.90-0.84(m, 2H), 0.83 (d, J=6.7 Hz, 3H), 0.76 (d, J=7.0 Hz, 3H), 0.69 (d, J=5.7Hz, 3H), 0.17-0.05 (m, 18H); ¹³C NMR (75 MHz, CDCl₃) δ 211.7, 159.8,144.4, 134.3, 133.1, 131.4, 130.9, 128.6, 127.9, 127.6, 127.1, 126.8,126.4, 113.4, 100.8, 86.7, 82.9, 81.0, 72.8, 66.5, 65.2, 55.2, 48.3,43.0, 42.2, 39.8, 38.3, 35.2, 35.1, 31.9, 31.3, 29.7, 26.2, 26.0, 25.9,19.6, 18.6, 18.4, 18.1, 16.3, 14.6, 12.1, 9.7, −2.9, −3.5, −3.6, −4.0,−4.1, −4.2; LRMS (ESI) 1211.8 [M+Na]+, 577.3, 463.3, 413.3, 359.2,316.9, 284.3; HRMS (ESI) calcd for C₇₂H₁₁₂O₈Si₃Na 1211.7563 [M+Na]+,found 1211.7629; [α]²⁰ _(D) −4.3 (c 1.0, CHCl₃).

(2S,3R,6S,8R,9R,10S,11Z,13S,15S,16S,17E)-9,13,15-tris(tert-Butyldimethylsilyloxy)-2-((4S,5S)-2-(4-methoxyphenyl)-5-methyl-1,3-dioxan-4-yl)-6,8,10,16-tetramethyl-19-(trityloxy)nonadeca-11,17-dien-3-ol(91). NaBH₄ (0.074 g, 1.96 mmol) was added to a solution of ketone 90(1.55 g, 1.30 mmol) in MeOH (21 mL) at 0° C. After stirring for 2 h at0° C., the reaction mixture was evaporated and water (30 mL) was added.The reaction mixture was extracted with ether (2×40 mL) and washed withbrine (50 mL), dried over MgSO₄ and concentrated in vacuo. The residuewas purified by flash chromatography (EtOAc/hexane 1:9) to yield 1.02 gof major product β (less polar, 62%) and 0.60 g (more polar, 36%) ofminor product α as colorless oils: (91β) IR (CHCl₃) 3540, 2956, 2929,2855, 1615, 1518, 1461, 1385, 1252, 1074, 835, 773, 706 cm⁻¹; ¹H NMR(300 MHz, CDCl₃) δ 7.54-7.50 (m, 6H), 7.42 (m, 2H), 7.37-7.25 (m, 9H),6.94-6.91 (m, 2H), 5.88 (dd, J=15.7, 6.0 Hz, 1H), 5.61 (dt, J=16.0, 5.7Hz, 1H), 5.56 (s, 1H), 5.50 (m, 1H), 5.37 (dd, J=10.8, 8.6 Hz, 1H), 4.60(m, 1H), 4.17 (dd, J=11.2, 4.6 Hz, 1H), 3.96 (m, 1H), 3.87 (m, 1H), 3.84(s, 3H), 3.74 (m, 1H), 3.64-3.53 (m, 3H), 3.32 (m, 1H), 3.20 (br, 1H),2.67 (m, 1H), 2.44 (m, 1H), 2.18 (m, 1H), 1.83 (m, 1H), 1.67-1.51 (m,2H), 1.50-1.32 (m, 3H), 1.26 (m, 1H), 1.08 (d, J=6.8 Hz, 3H), 1.07 (m,2H), 1.06 (d, J=7.0 Hz, 3H), 1.04 (d, J=7.4 Hz, 3H), 0.98-0.85 (m, 2H),0.82 (d, J=6.7 Hz, 3H), 0.81 (d, J=6.7 Hz, 3H), 0.77 (d, J=6.0 Hz, 3H),0.18-0.09 (m, 18H); ¹³C NMR (75 MHz, CDCl₃) δ 160.0, 144.5, 144.4,134.4, 132.9, 131.6, 130.7, 128.6, 127.6, 127.2, 126.8, 126.7, 126.4,113.6, 101.2, 89.1, 86.7, 81.1, 76.8, 73.1, 72.8, 66.5, 55.2, 43.0,42.3, 39.9, 37.2, 35.3, 35.1, 34.7, 32.3, 30.4, 30.2, 26.2, 26.1, 25.9,19.6, 18.8, 18.4, 18.13, 18.10, 16.3, 14.6, 11.9, 5.5, −2.8, −3.56,−3.61, −4.0, −4.1, −4.16, −4.25; LRMS (API-ES) 1213.6 [M+Na]⁺, 557.0,359.2, 243.1; HRMS (ESI) calcd for C₇₂H₁₁₄O₈Si₃Na 1213.7719 [M+Na]+,found 1213.7717; [α]²⁰ _(D) −0.68 (c 7.1, CHCl₃): (91α) IR (CHCl₃) 3531,2956, 2929, 2855, 1615, 1518, 1462, 1383, 1252, 1075, 836, 773 cm⁻¹; ¹HNMR (300 MHz, CDCl₃) δ 7.53-7.49 (m, 6H), 7.44-7.41 (m, 2H), 7.36-7.24(m, 9H), 6.94-6.91 (m, 2H), 5.86 (dd, J=15.7, 6.0 Hz, 1H), 5.60 (dt,J=15.7, 5.7 Hz, 1H), 5.54 (s, 1H), 5.56-5.47 (m, 1H), 5.36 (dd, J=11.0,8.6 Hz, 1H), 4.60 (m, 1H), 4.17 (dd, J=11.2, 4.6 Hz, 1H), 3.97-3.91 (m,2H), 3.84 (s, 3H), 3.62 (d, J=4.9 Hz, 2H), 3.61-3.53 (m, 2H), 3.32 (m,1H), 2.67 (m, 1H), 2.44 (m, 1H), 2.16 (m, 1H), 1.82 (m, 1H), 1.72-1.50(m, 4H), 1.42-1.33 (m, 2H), 1.32-1.22 (m, 2H), 1.14 (d, J=7.1 Hz, 3H),1.06 ((d, J=7.0 Hz, 3H), 1.03 (d, J=7.0 Hz, 3H), 0.97-0.92 (m, 27H),0.90-0.85 (m, 2H), 0.81 (d, J=6.4 Hz, 3H), 0.79 (d, J=6.6 Hz, 3H), 0.76(d, J=5.7 Hz, 3H), 0.17-0.09 (m, 18H); ¹³C NMR (75 MHz, CDCl₃) δ 160.0,144.6, 144.4, 134.4, 133.0, 131.6, 131.1, 128.7, 127.7, 127.6, 127.3,126.8, 126.7, 126.4, 113.6, 101.0, 86.7, 82.8, 81.2, 75.1, 73.3, 72.8,66.6, 65.2, 55.2, 43.0, 42.3, 39.9, 37.9, 35.3, 35.1, 34.6, 33.4, 30.3,26.3, 26.1, 26.0, 19.7, 19.0, 18.4, 18.1, 16.4, 14.6, 11.9, 11.1, −2.8,−3.5, −4.0, −4.07, −4.13; LRMS (ESI) 1213.8 [M+Na]+, 633.2, 359.2; HRMS(ESI) calcd for C₇₂H₁₁₄O₈Si₃Na 1213.7719 [M+Na]+, found 1213.7766; [α]²⁰_(D) −1.4 (c 4.7, CHCl₃).

(4S,5S)-4-((2R,3R,6S,8R,9R,10S,11Z,13S,15S,16S,17E)-3,9,13,15-tetrakis(tert-Butyldimethylsilyloxy)-6,8,10,16-tetramethyl-19-(trityloxy)nonadeca-11,17-dien-2-yl)-2-(4-methoxyphenyl)-5-methyl-1,3-dioxane(92). TBSOTf (0.30 mL, 2.57 mmol) was added to a stirred solution ofalcohol 91p (1.02 g, 0.86 mmol) and 2,6-lutidine (0.20 mL, 1.71 mmol) inCH₂Cl₂ (17 mL) at 0° C. and the reaction mixture was stirred for 1 h atambient temperature. The reaction mixture was quenched by the additionof water (50 mL). The reaction mixture was extracted by CH₂Cl₂ and driedover MgSO₄ followed by the evaporation of the solution under reducedpressure. The residue was purified by short column chromatography(hexane/EtOAc 9:1) to yield product (0.97 g, 86%) as a colorless oil: IR(CHCl₃) 2955, 2928, 2856, 1615, 1518, 1471, 1462, 1387, 1251, 1074,1038, 835, 773 cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ 7.52-7.46 (m, 6H),7.45-7.42 (m, 2H), 7.35-7.22 (m, 9H), 6.92-6.89 (m, 2H), 5.86 (dd,J=15.7, 6.0 Hz, 1H), 5.59 (dt, J=15.7, 4.9 Hz, 1H), 5.48 (m, 1H), 5.47(s, 1H), 5.36 (dd, J=11.1, 8.6 Hz, 1H), 4.58 (m, 1H), 4.15 (dd, J=11.2,4.6 Hz, 1H), 3.96 (m, 1H), 3.81 (s, 3H), 3.73-3.66 (m, 2H), 3.60 (d,J=5.6 Hz, 2H), 3.55 (m, 1H), 3.19 (m, 1H), 2.65 (m 1H), 2.42 (m, 1H),2.07 (m, 1H), 1.91 (m, 1H), 1.57 (m, 2H), 1.40-1.21 (m, 3H), 1.14 (m,1H), 1.06 (d, J=6.7 Hz, 3H), 1.04 (d, J=5.9 Hz, 3H), 1.02 (d, J=6.9 Hz,3H), 0.96-0.92 (m, 36H), 0.88-0.84 (m, 3H), 0.80 (m, 1H), 0.77 (d, J=6.5Hz, 3H), 0.76 (d, J=6.4 Hz, 3H), 0.71 (d, J=5.1 Hz, 3H), 0.16-0.03 (m,24H); ¹³C NMR (75 MHz, CDCl₃) δ 159.7, 144.6, 144.4, 134.4, 133.2,131.7, 131.4, 128.7, 127.7, 127.2, 126.8, 126.4, 113.4, 100.4, 86.7,81.8, 81.4, 75.0, 73.3, 72.8, 66.5, 65.2, 55.2, 43.1, 42.3, 39.7, 38.9,35.3, 35.0, 34.0, 31.2, 30.7, 30.6, 26.2, 26.1, 26.00, 25.95, 19.5,19.1, 18.4, 18.13, 18.10, 16.5, 14.5, 12.4, 10.6, −2.8, −3.4, −3.95,−3.98, −4.2, −4.3; LRMS (ESI) 1327.8 [M+Na]+, 977.8, 739.6; HRMS (ESI)calcd for C₇₈H₁₂₈O₈Si₄Na 1327.8584 [M+Na]+, found 1327.8534; [α]²⁰ _(D)+6.7 (c 0.65, CHCl₃).

(2S,3S,4R,5R,8S,10R,11R,12S,13Z,15S,17S,18S,19E)-3-(4-Methoxybenzyloxy)-5,11,15,17-tetrakis(tert-butyldimethylsilyloxy)-2,4,8,10,12,18-hexamethyl-21-(trityloxy)henicosa-13,19-dien-1-ol(93). DIBAL (1.0 M in hexane, 7.4 mL, 7.4 mmol) was added to a stirredsolution of TBS protected acetal 92 (0.97 g, 0.74 mmol) in anhydrousCH₂Cl₂ (3 mL), under an atmosphere of N₂ at 0° C. dropwise. Afterstirring for additional 30 min at 0° C., the reaction mixture wasquenched by the careful addition of aqueous sat'd potassium sodiumtartrate solution (30 mL) and stirred for 3 h at room temperature. Theorganic layer was separated, and the aqueous layer was extracted withCH₂Cl₂ (20 mL). The combined organic layers were washed with brine anddried over MgSO₄ followed by the evaporation of the organic solutionunder reduced pressure. The residue was purified by columnchromatography (EtOAc/hexane 1:9) to obtain 93 (0.94 g, 97%) as acolorless oil: IR (CHCl₃) 3501, 2956, 2929, 2856, 1613, 1514, 1471,1462, 1251, 1075, 835, 773, 705 cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ7.55-7.51 (m, 6H), 7.37-7.25 (m, 11H), 6.94-6.92 (m, 2H), 5.90 (dd,J=15.7, 5.9 Hz, 1H), 5.62 (dt, J=15.6, 5.6 Hz, 1H), 5.56-5.48 (m, 1H),5.40 (dd, J=11.2, 8.5 Hz, 1H), 4.61 (m, 1H), 4.60 (s, 2H), 3.99 (m, 1H),3.90 (m, 1H), 3.83 (s, 3H), 3.69 (m, 1H), 3.64 (d, J=5.3 Hz, 1H), 3.53(m, 1H), 3.31 (m, 1H), 2.99 (m 1H), 2.70 (m, 1H), 2.47 (m, 1H), 2.00 (m,2H), 1.65-1.52 (m, 3H), 1.45-1.37 (m, 1H), 1.33 (m, 1H), 1.30 (m, 1H),1.20 (d, J=6.9 Hz, 3H), 1.10 (d, J=6.6 Hz, 3H), 1.09 (d, J=6.9 Hz, 3H),1.05 (d, J=7.0 Hz, 3H), 1.00-0.96 (m, 36H), 0.92-0.86 (m, 2H), 0.82 (d,J=6.6 Hz, 3H), 0.76 (d, J=5.5 Hz, 3H), 0.19-0.11 (m, 24H); ¹³C NMR (75MHz, CDCl₃) δ 159.2, 144.5, 144.4, 134.3, 133.1, 131.5, 130.5, 129.2,128.6, 127.6, 126.8, 126.4, 113.8, 86.7, 86.0, 81.1, 75.3, 73.6, 72.8,66.5, 65.1, 65.0, 55.1, 43.0, 42.3, 40.5, 40.0, 36.8, 35.2, 35.1, 34.0,32.1, 30.4, 26.2, 26.1, 26.0, 25.9, 19.6, 18.9, 18.4, 18.1, 16.5, 15.8,14.6, 9.9, −2.8, −3.4, −3.5, −3.8, −4.0, −4.2, −4.4; LRMS (ESI) 1329.8[M+Na]+, 1087.7, 801.5, 669.4, 537.3, 480.2, 359.2, 243.1; HRMS (ESI)calcd for C₇₈H₁₃₀O₈Si₄Na 1329.8741 [M+Na]+, found 1329.8778; [α]²⁰ _(D)−9.9 (c 0.36, CHCl₃).

((2E,4S,5S,7S,8Z,10S,11R,12R,14S,17R,18R,19S,20S,21Z)-19-(4-Methoxybenzyloxy)-7,11,17-tris(tert-butyldimethylsilyloxy)-5-(tert-butyldimethylsilyloxy))-4,10,12,14,18,20-hexamethyltetracosa-2,8,21,23-tetraenyloxy)triphenylmethane(94). The alcohol 93 (0.94 g, 0.72 μmol) in CH₂Cl₂ (20 mL) was treatedwith Dess-Martin periodinane (0.46 g, 1.08 μmol). After 1 h, the mixturewas quenched with saturated NaHCO₃ (20 mL) and Na₂S₂O₃ (20 mL). Theaqueous layer was extracted with ethyl ether (20 mL×2) and the combinedextracts were dried over anhydrous MgSO₄. Filtration and concentrationfollowed by short flash column chromatography (hexane/EtOAc 9:1) toremove Dess-Martin residue provided crude aldehyde as a colorless oil,which was used for the next reaction without further purification. To astirred solution of the above crude aldehyde and 1-bromoallyltrimethylsilane (0.89 g) in anhydrous THF (18 mL) under an atmosphere ofN₂ at room temperature was added CrCl₂ (0.73 g, 5.94 mmol), and themixture was stirred for additional 14 h at ambient temperature. Thereaction mixture was diluted with hexane followed by filtration throughcelite. After the evaporation of the solvent under reduced pressure, theresidue was purified by short silica gel column chromatography usingEtOAc/hexane (1:9) as an eluent. The foregoing product in THF (40 mL)was cooled to 0° C. and NaH (95% w/w, 0.36 g, 14.4 mmol) was added inone portion. The ice bath was removed after 15 min and the mixture wasstirred for 2 h at ambient temperature. The reaction mixture was cooledto 0° C., quenched with H₂O (5 mL), extracted with ethyl ether (20mL×2). The combined organic layers were washed with brine and dried overMgSO₄ followed by the evaporation of the organic solution under reducedpressure. The residue was purified by column chromatography(hexane/EtOAc 98:2) to obtain 94 (0.81 g, 85% for 3 steps) as acolorless oil: IR (CHCl₃) 2955, 2928, 2856, 1614, 1514, 1471, 1462,1249, 1076, 835, 772, 705 cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ 7.60-7.56 (m,6H), 7.43-7.27 (m, 11H), 6.99-6.96 (m, 1H), 6.71 (ddd, J=16.9, 10.6,10.5 Hz, 1H), 6.14 (t, J=11.0 Hz, 1H), 5.97 (dd, J=15.7, 5.9 Hz, 1H),5.82-5.77 (m, 1H), 5.74-5.70 (m, 1H), 5.68-5.62 (m, 1H), 5.61-5.56 (m,1H), 5.46 (dd, J=11.1, 8.6 Hz, 1H), 5.28 (d, J=16.9 Hz, 1H), 5.20 (d,J=10.3 Hz, 1H), 4.66 (m, 3H), 4.05 (m, 1H), 3.86 (s, 3H), 3.76 (m, 1H),3.69 (d, J=5.2 Hz, 1H), 3.48 (m, 1H), 3.35 (m, 1H), 3.15 (m, 1H), 2.76(m, 1H), 2.53 (m, 1H), 2.34 (m, 1H), 1.82 (m, 1H), 1.70-1.57 (m, 3H),1.56-1.32 (m, 3H), 1.25 (d, J=6.8 Hz, 3H), 1.14 (d, J=7.1 Hz, 3H), 1.12(m, 2H), 1.11 (d, J=7.1 Hz, 3H), 1.08-1.03 (m, 36H), 0.98-0.90 (m, 2H),0.86 (d, J=6.6 Hz, 3H), 0.76 (d, J=5.1 Hz, 3H), 0.25-0.13 (m, 24H); ¹³CNMR (75 MHz, CDCl₃) δ 159.0, 146.2, 144.6, 144.4, 134.5, 134.3, 133.2,132.4, 131.4, 130.2, 129.0, 128.7, 127.7, 126.8, 126.5, 117.2, 113.7,86.7, 84.5, 81.3, 75.1, 72.9, 66.6, 65.2, 55.1, 43.0, 42.3, 40.6, 40.2,35.6, 35.25, 35.19, 33.9, 32.6, 30.3, 26.3, 26.1, 26.04, 25.99, 19.6,18.9, 18.4, 18.2, 16.6, 14.7, 9.2, −2.8, −3.36, −3.4, −3.5, −3.9, −4.1,−4.4; LRMS (ESI) 1351.8 [M+Na]+, 837.1, 763.1, 689. 541.0; HRMS (ESI)calcd for C₈₁H₁₃₂O₇Si₄Na 1351.8948 [M+Na]+, found 1351.8973; [α]²⁰ _(D)+0.4 (c 0.51, CHCl₃).

(2E,4S,5S,7S,8Z,10S,11R,12R,14S,17R,18R,19S,20S,21Z)-19-(4-Methoxybenzyloxy)-5,7,11,17-tetrakis(tert-butyldimethylsilyloxy)-4,10,12,14,18,20-hexamethyltetracosa-2,8,21,23-tetraen-1-ol(95). ZnBr₂ solution (0.42 g in 5 mL CH₂Cl₂ and 0.8 mL of MeOH) wasadded to a stirred solution of trityl ether 94 (0.50 g, 0.38 μmol) inMeOH (3 mL), CH₂Cl₂ (18 mL) at 0° C. dropwise for 30 min. After 4 h, thereaction mixture was quenched with saturated NaHCO₃ solution (20 mL) andextracted with Et₂O (10 mL×2). The organic phase was separated, driedwith MgSO₄ and concentrated. The residue was purified by flashchromatography (EtOAc/hexane 1:9) to yield 0.34 g of product 95 (83%) asa colorless oil: IR (CHCl₃) 3410, 2956, 2929, 2856, 1613, 1514, 1471,1251, 1076, 836, 773 cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ 7.31-7.29 (m, 2H),6.90-6.87 (m, 2H), 6.60 (ddd, J=16.8, 10.6, 10.5 Hz, 1H), 6.02 (t,J=11.0 Hz, 1H), 5.79 (dd, J=15.6, 5.8 Hz, 1H), 5.62 (d, J=9.3 Hz, 1H),5.60 (m, 1H), 5.47 (t, J=10.3 Hz, 1H), 5.32 (dd, J=10.7, 8.9 Hz, 1H),5.18 (d, J=16.8 Hz, 1H), 5.10 (d, J=10.2 Hz, 1H), 4.54 (m, 3H), 4.07 (d,J=5.9 Hz, 2H), 3.89 (m, 1H), 3.81 (s, 3H), 3.64 (m, 1H), 3.35 (m, 1H),3.24 (br, 1H), 3.00 (m, 1H), 2.61 (m, 1H), 2.40 (m, 1H), 1.68 (m, 1H),1.55-1.42 (m, 3H), 1.38-1.21 (m, 3H), 1.12 (d, J=6.7 Hz, 3H), 1.02-0.99(m, 3H), 0.98 (d, J=7.0 Hz, 3H), 0.94-0.89 (m, 40H), 0.79 (d, J=6.9 Hz,3H), 0.76 (d, J=6.3 Hz, 3H), 0.11-0.06 (m, 24H); ¹³C NMR (75 MHz, CDCl₃)δ 159.0, 134.9, 134.5, 133.1, 132.4, 131.5, 131.4, 129.1, 128.9, 128.7,117.2, 113.7, 84.5, 81.3, 75.1, 72.7, 66.4, 64.1, 55.3, 42.7, 42.0,40.5, 40.4, 35.5, 35.23, 35.20, 33.9, 32.6, 30.5, 26.3, 26.03, 26.00,25.96, 19.7, 18.9, 18.8, 18.5, 18.2, 18.1, 16.6, 14.7, 9.2, −2.8, −3.47,−3.53, 4.03, 4.05, −4.2, −4.5, −4.7; LRMS (ESI) 1109.7 [M+Na]+, 945.3,797.3, 723.2, 577.4, 499.2, 413.3, 359.3; HRMS (ESI) calcd forC₆₂H₁₁₈O₇Si₄Na 1109.7852 [M+Na]+, found 1109.7898; [α]²⁰ _(D) −2.0 (c2.6, CHCl₃).

(2Z,4E,6S,7S,9S,1Z,12S,13R,14R,16S,19R,20R,21S,22S,23Z)-Methyl-21-(4-methoxybenzyloxy)-7,9,13,19-tetrakis(tert-butyldimethylsilyloxy)-6,12,14,16,20,22-hexamethylhexacosa-2,4,10,23,25-pentaenoate(96). The alcohol 95 (0.34 g, 0.31 μmol) in CH₂Cl₂ (20 mL) was treatedwith Dess-Martin periodinane (0.20 g, 0.47 μmol). After 1 h, the mixturewas quenched with saturated NaHCO₃ (5 mL) and Na₂S₂O₃ (5 mL). Theaqueous layer was extracted with ethyl ether (10 mL×2) and the combinedextracts were dried over anhydrous MgSO₄. Filtration and concentrationfollowed by short flash column chromatography (hexane/EtOAc 9:1) toremove the Dess-Martin residue provided the crude aldehyde as acolorless oil, which was used for the next reaction without furtherpurification. To a stirred solution ofbis(2,2,2-trifluoroethyl)-(methoxycarbonylmethyl) phosphate (0.080 mL,0.37 μmol), 18-crown-6 (0.41 g, 1.55 mmol) in THF (6 mL) cooled to −78°C. was added dropwise potassium bis(trimethylsilyl)amide (0.75 mL, 0.37μmol, 0.5M solution in toluene). Thereafter the above aldehyde in THF (1mL) was added and the solution was stirred for 4 h at −78° C. Thereaction mixture was quenched by addition of a sat'd NH₄Cl solution (5mL) and diluted with diethyl ether (20 mL). The layers were separatedand organic phase was washed with brine (30 mL) and dried with MgSO₄,filtered, and concentrated. The residue was purified by flashchromatography (EtOAc/hexane 5:95) to obtain (E,Z)-doubly unsaturatedester 96 (0.32 g, 90% for 2 steps) as a colorless oil: IR (CHCl₃) 2956,2929, 2885, 1722, 1641, 1514, 1471, 1250, 1174, 1075, 836, 773 cm⁻¹; ¹HNMR (300 MHz, CDCl₃) δ 7.34 (dd, J=15.5, 11.2 Hz, 1H), 7.29-7.26 (m,2H), 6.87-6.84 (m, 2H), 6.56 (ddd, J=17.0, 10.6, 10.5 Hz, 1H), 6.52 (t,J=11.4 Hz, 1H), 6.19 (dd, J=15.5, 6.4 Hz, 1H), 5.99 (t, J=11.0 Hz, 1H),5.57 (t, J=10.5 Hz, 1H), 5.54 (d, J=11.3 Hz, 1H), 5.42 (m, 1H), 5.30 (m,1H), 5.15 (d, J=16.8 Hz, 1H), 5.07 (d, J=10.1 Hz, 1H), 4.51 (m, 3H),3.92 (m, 1H), 3.78 (s, 3H), 3.70 (s, 3H), 3.61 (m, 1H), 3.32 (dd, J=7.9,2.8 Hz, 1H), 3.20 (m, 1H), 2.97 (m, 2H), 2.57 (m, 2H), 1.65 (m, 1H),1.56-1.39 (m, 3H), 1.29-1.16 (m, 3H), 1.10 (d, J=6.8 Hz, 3H), 1.03 (d,J=6.9 Hz, 3H), 0.98 (d, J=7.0 Hz, 3H), 0.94 (d, J=6.9 Hz, 3H), 0.93-0.83(m, 39H), 0.77 (m, 1H), 0.91 (s, 9H), 0.87 (s, 9H), 0.83 (d, J=6.4 Hz,3H), 0.82 (d, J=6.0 Hz, 3H), 0.13 (s, 3H), 0.76 (d, J=6.6 Hz, 3H), 0.71(d, J=5.9 Hz, 3H), 0.10-0.02 (m, 24H); ¹³C NMR (75 MHz, CDCl₃) δ 166.8,159.0, 147.2, 145.6, 134.5, 133.1, 132.4, 131.5, 131.4, 129.0, 128.9,126.4, 117.1, 115.1, 113.7, 84.4, 81.3, 75.0, 72.8, 72.7, 66.4, 55.2,50.9, 42.9, 42.6, 40.5, 40.2, 35.3, 35.2, 33.8, 32.6, 30.5, 26.3, 26.0,25.9, 19.6, 18.9, 18.8, 18.4, 18.2, 18.1, 16.7, 14.5, 9.2, −2.8, −3.4,−3.5, −3.6, −4.07, −4.14, −4.24, −4.49; LRMS (ESI) 1163.8 [M+Na]+,1107.9, 782.5; HRMS (ESI) calcd for C₆₅H₁₂₀O₈Si₄Na 1163.7958 [M+Na]+,found 1163.8004; [α]²⁰ _(D) −27.3 (c 5.0, CHCl₃).

(2Z,4E,6S,7S,9S,10Z,12S,13R,14R,16S,19R,20R,21S,22S,23Z)-Methyl-7,9,13,19-tetrakis(tert-butyldimethylsilyloxy)-21-hydroxy-6,12,14,16,20,22-hexamethylhexacosa-2,4,10,23,25-pentaenoate(97). The ester 96 (0.15 g, 0.14 μmol) was added to CH₂Cl₂ (5 mL) andH₂O (0.2 mL) and DDQ (34 mg, 0.15 μmol) was added at 0° C. After 1 h ofstirring at 0° C., the reaction mixture was quenched by adding sat'dNaHCO₃ (5 mL). The organic phase was washed by sat'd NaHCO₃ solution(3×10 mL) and brine, dried over MgSO₄ and concentrated. Purification byflash column chromatography (EtOAc/hexane 1:9) furmished 97 (0.12 g,90%) as a colorless oil: IR (CHCl₃) 3540, 2956, 2929, 2856, 1641, 1601,1471, 1462, 1407, 1379, 1361, 1255, 1174, 1089, 1004, 836, 773 cm⁻¹; ¹HNMR (300 MHz, CDCl₃) δ 7.33 (dd, J=15.5, 11.2 Hz, 1H), 6.61 (ddd,J=16.9, 10.5, 10.4 Hz, 1H), 6.51 (t, J=11.4 Hz, 1H), 6.17 (dd, J=15.5,5.9 Hz, 1H), 6.07 (t, J=11.0 Hz, 1H), 5.54 (d, J=11.3 Hz, 1H), 5.45-5.37(m, 2H), 5.28 (m, 1H), 5.18 (d, J=16.8 Hz, 1H), 5.09 (d, J=10.1 Hz, 1H),4.51 (m, 1H), 3.91 (m, 1H), 3.74 (m, 1H), 3.69 (s, 3H), 3.45 (m, 1H),3.23 (m, 1H), 3.76 (m, 1H), 2.56 (m, 2H), 2.29 (br, 1H), 1.68 (m, 1H),1.56-1.41 (m, 3H), 1.34-1.17 (m, 3H), 1.02 (d, J=6.9 Hz, 3H), 0.97 (d,J=6.9 Hz, 3H), 0.94 (d, J=6.8 Hz, 3H), 0.90-0.84 (m, 40H), 0.81 (d,J=5.8 Hz, 3H), 0.77 (d, J=6.5 Hz, 3H), 0.76 (d, J=6.2 Hz, 3H), 0.08-0.01(m, 24H); ¹³C NMR (75 MHz, CDCl₃) δ 166.8, 147.3, 145.5, 135.3, 133.0,132.3, 131.5, 129.9, 126.4, 117.6, 115.2, 81.3, 77.5, 76.7, 72.7, 66.4,50.9, 42.9, 42.6, 40.1, 37.9, 36.1, 35.4, 35.2, 33.8, 32.2, 30.6, 26.2,26.0, 25.9, 19.6, 19.0, 18.4, 18.10, 18.05, 17.7, 16.6, 14.4, 6.9, −2.8,−3.5, −3.6, −3.7, −4.1, −4.15, −4.21, −4.4; LRMS (ESI) 1043.7 [M+Na]+,889.8, 757.6, 625.5, 544.3, 364.4; HRMS (ESI) calcd for C₅₇H₁₁₂O₇Si₄Na1043.7383 [M+Na]+, found 1043.7433; [α]²⁰ _(D) −40.3 (c 2.1, CHCl₃).

(2Z,4E,6S,7S,9S,10Z,12S,13R,14R,16S,19R,20R,21S,22S,23Z)-7,9,13,19-tetrakis(tert-Butyldimethylsilyloxy)-21-hydroxy-6,12,14,16,20,22-hexamethylhexacosa-2,4,10,23,25-pentaenoicacid (98). 1N aqueous KOH solution (1.2 mL) was added to a stirriedsolution of the above 97 (0.12 g, 0.12 μmol) in EtOH (12 mL), THF (1 mL)and the mixture was refluxed gently until the ester disappeared (about 5h) as determined by TLC analysis. The ethanolic solution wasconcentrated and then diluted with ether (4 mL). After the solution wasacidified to pH3 with 1N HCl solution, organic phase was separated andaqueous phase was extracted with Et₂O (2×5 mL). The combined organicphases were dried with MgSO₄, concentrated and used without furtherpurification: IR (CHCl₃) 2957, 2929, 2857, 1692, 1471, 1462, 1254, 1089,836, 773 cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ 7.34 (dd, J=15.1, 11.4 Hz, 1H),6.64 (ddd, J=16.0, 10.8, 10.5 Hz, 1H), 6.61 (t, J=11.2 Hz, 1H), 6.22(dd, J=15.4, 6.0 Hz, 1H), 6.09 (t, J=11.0 Hz, 1H), 5.58 (d, J=11.3 Hz,1H), 5.49-5.39 (m, 2H), 5.34-5.28 (m, 1H), 5.20 (d, J=16.7 Hz, 1H), 5.11(d, J=10.2 Hz, 1H), 4.55 (m, 1H), 3.95 (m, 1H), 3.76 (m, 1H), 3.50 (m,1H), 3.27 (m, 1H), 2.81 (m, 1H), 2.58 (m, 2H), 1.71 (m, 1H), 1.57-1.50(m, 3H), 1.44-1.31 (m, 3H), 1.25 (d, J=7.3 Hz, 3H), 1.21 (d, J=6.1 Hz,3H), 1.04 (d, J=6.9 Hz, 3H), 0.99 (d, J=7.0 Hz, 3H), 0.96-0.89 (m, 40H),0.81 (d, J=6.2 Hz, 3H), 0.79 (d, J=5.9 Hz, 3H), 0.11-0.05 (m, 24H); ¹³CNMR (75 MHz, CDCl₃) δ 171.1, 148.1, 147.3, 135.2, 132.8, 132.3, 131.6,129.9, 126.6, 117.6, 115.0, 81.3, 77.6, 72.7, 66.4, 58.3, 43.0, 42.6,40.1, 37.9, 36.0, 35.4, 35.2, 33.8, 32.2, 30.6, 26.3, 26.0, 25.9, 25.2,19.6, 19.0, 18.4, 18.09, 18.05, 17.7, 16.6, 14.5, 7.0, −2.8, −3.45,−3.54, −3.7, −4.1, −4.2, −4.4; LRMS (ESI) 1029.7 [M+Na]+, 915.7, 897.7;HRMS (ESI) calcd for C₅₆H₁₁₀O₇Si₄Na 1029.7226 [M+Na]+, found 1029.7257;[α]²⁰ _(D) −41.7 (c 1.4, CHCl₃).

8(S),10(S),14(R),20(R)-tetrakis(tert-Butyldimethylsilyloxy)-7(S),13(S),15(R),17(S),21(S)-pentamethyl-22(S)-(1(S)-methylpenta-2,4-dienyl)oxacyclodocosa-3,5,11-trien-2-one(99). A solution of above acid 98 in THF (2 mL) was treated at 0° C.with Et₃N (0.10 mL, 0.72 μmol) and 2,4,6-trichlorobenzoyl chloride(0.095 mL, 0.60 μmol). The reaction mixture was stirred at 0° C. for 30min and then added to 4-DMAP (60 mL, 0.02 M solution in toluene) at 25°C. and stirred overnight. The reaction mixture was concentrated, Et₂O(10 mL) was added and the crude was washed with 0.5 N HCl (2×10 mL),dried over MgSO₄. Purification by flash column chromatography(EtOAc/hexane 2:98) furnished macrolactone 99 (93 mg, 78% for 2 steps)as a colorless oil: IR (CHCl₃) 2957, 2929, 2856, 1745, 1715, 1581, 1471,1369, 1270, 1117, 1082, 836, 773 cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ 7.11(dd, J=15.3, 10.5 Hz, 1H), 6.59 (ddd, J=16.8, 10.7, 10.5 Hz, 1H), 6.22(dd, J=15.4, 6.0 Hz, 1H), 6.07 (dd, J=15.4, 10.6 Hz, 1H), 5.92 (t,J=10.9 Hz, 1H), 5.70 (d, J=15.4 Hz, 1H), 5.46 (t, J=10.5 Hz, 1H),5.35-5.27 (m, 2H), 5.20 (d, J=8.4 Hz, 1H), 5.12 (d, J=16.8 Hz, 1H), 5.04(d, J=10.3 Hz, 1H), 4.53 (m, 1H), 3.91 (m, 1H), 3.41 (m, 1H), 3.19 (m,1H), 2.94 (m, 1H), 2.55 (m, 2H), 1.94 (m, 1H), 1.40-1.29 (m, 3H),1.26-1.15 (m, 3H), 1.00-0.85 (m, 52H), 0.74 (d, J=6.7 Hz, 3H), 0.63 (d,J=6.2 Hz, 3H), 0.08-0.00 (m, 24H); ¹³C NMR (75 MHz, CDCl₃) δ 166.9,144.93, 144.88, 136.0, 135.0, 133.5, 132.4, 130.7, 129.3, 120.2, 117.2,80.3, 75.7, 73.9, 72.7, 66.3, 42.4, 41.0, 40.6, 39.3, 36.5, 35.8, 35.1,34.5, 31.9, 29.7, 26.2, 26.0, 25.9, 21.6, 19.8, 19.7, 18.4, 18.11,18.07, 17.9, 14.9, 11.3, −2.6, −3.6, −3.8, −4.2, −4.5, −4.6; LRMS (ESI)1011.8 [M+Na]+, 857.7, 725.6, 633.2, 413.3, 375.3; HRMS (ESI) calcd forC₅₆H₁₀₈O₆Si₄Na 1011.7121 [M+Na]+, found 1011.7148; [α]²⁰ _(D) −16.9 (c1.24, CHCl₃).

8(S),10(S),14(R),20(R)-Tetrahydroxy-7(S),13(S),15(R),17(S),21(S)-pentamethyl-22(S)-(1S)-methylpenta-2,4-dienyl)-oxacyclodocosa-3(E),5(E),11(Z)-trien-2-one(100, YSS665-2). 3 N HCl (10 mL, prepared by adding 2.5 mL of conc. HClto 7.5 mL MeOH) was added to a stirred solution of the abovemacrolactone 99 (61 mg, 6.17 μmol) in THF (3 mL) at 0° C. After 24 h atroom temperature, the reaction mixture was diluted with EtOAc (4 mL) andH₂O (4 mL) and the organic phase was separated and aqueous phase wasextracted with EtOAc (2×4 mL). The combined organic phases were washedwith sat'd NaHCO₃ (10 mL), dried with MgSO₄, concentrated and theresidue was purified by flash chromatography (EtOAc/hexane 3:2) to yieldthe product 100 (8.2 mg, 25%) as a colorless oil: IR (CHCl₃) 3404, 2962,2916, 1692, 1639, 1455, 1244, 1061, 1001 cm⁻¹; ¹H NMR (600 MHz, CD₃OD) δ7.15 (dd, J=15.3, 10.5 Hz, 1H), 6.64 (ddd, J=16.8, 10.6, 10.3 Hz, 1H),6.29 (dd, J=15.4, 6.3 Hz, 1H), 6.22 (dd, J=15.5, 10.5 Hz, 1H), 5.92 (t,J=10.9 Hz, 1H), 5.72 (d, J=15.3 Hz, 1H), 5.44-5.37 (m, 2H), 5.25 (t,J=10.3 Hz, 1H), 5.13 (dd, J=16.8, 1.8 Hz, 1H), 5.06 (d, J=10.8 Hz, 1H),5.04 (dd, J=9.1, 1.8 Hz, 1H), 4.68 (ddd, J=9.9, 7.2, 2.4 Hz, 1H), 3.82(ddd, J=9.2, 6.2, 2.7 Hz, 1H), 3.40 (ddd, J=10.2, 6.2, 2.3 Hz, 1H), 3.06(m, 1H), 2.99 (dd, J=8.0, 3.3 Hz, 1H), 2.62 (m, 1H), 2.58 (m, 1H), 1.88(m, 1H), 1.62 (m, 1H), 1.55 (ddd, J=14.0, 10.5, 2.7 Hz, 1H), 1.38 (ddd,J=12.3, 9.6, 2.7 Hz, 1H), 1.34-1.23 (m, 4H), 1.12 (d, J=7.0 Hz, 3H),1.06 (d, J=6.9 Hz, 3H), 1.04 (d, J=6.9 Hz, 3H), 1.00 (d, J=6.7 Hz, 3H),0.95-0.88 (m, 2H), 0.87-0.82 (m, 1H), 0.79 (d, J=5.3 Hz, 3H), 0.68 (d,J=6.7 Hz, 3H); ¹³C NMR (150 MHz, CD₃OD) δ 168.5, 147.7, 147.4, 135.7,134.4, 133.6, 131.7, 130.8, 129.1, 120.7, 118.0, 80.7, 76.9, 74.2, 72.8,65.9, 44.0, 42.5, 40.9, 39.5, 36.5, 36.3, 36.1, 35.5, 31.7, 31.2, 21.1,19.0, 17.9, 17.7, 15.7, 11.3; LRMS (ESI) 555.6 [M+Na]+, 541.4; HRMS(ESI) calcd for C₃₂H₅₂O₆ 555.3662 [M+Na]+, found 555.3684; [α]²⁰ _(D)−6.5 (c 0.17, MeOH).

(4S,5S)-4-((2R,3S,6S,8R,9R,10S,11Z,13S,15S,16S,17E)-3,9,13,15-tetrakis(tert-Butyldimethylsilyloxy)-6,8,10,16-tetramethyl-19-(trityloxy)nonadeca-11,17-dien-2-yl)-2-(4-methoxyphenyl)-5-methyl-1,3-dioxane(101). The same procedure for 92 was used with above 91α (0.60 g, 0.50μmol), TBSOTf (0.17 mL, 0.75 mmol) and 2,6-lutidine (0.12 mL, 1.0 mmol)to yield 0.61 g (93%) of the product by flash column chromatography(EtOAc/Hexane 1:9) as a colorless oil: IR (CHCl₃) 2956, 2928, 2856,1518, 1471, 1462, 1251, 1075, 835, 773 cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ7.56-7.48 (m, 8H), 7.38-7.26 (m, 9H), 6.97-6.94 (m, 1H), 5.91 (dd,J=15.6, 5.9 Hz, 1H), 5.63 (dt, J=15.7, 5.3 Hz, 1H), 5.58-5.50 (m, 1H),5.52 (s, 1H), 5.41 (dd, J=10.8, 8.6 Hz, 1H), 4.65 (m, 1H), 4.19 (dd,J=11.1, 4.5 Hz, 1H), 4.01 (m, 1H), 3.90 (m, 1H), 3.84 (s, 3H), 3.66 (d,J=5.0 Hz, 2H), 3.56 (t, J=11.1 Hz, 1H), 3.36 (m, 1H), 2.71 (m 1H), 2.48(m, 1H), 2.12 (m, 1H), 1.88 (m, 1H), 1.76-1.56 (m, 3H), 1.52-1.42 (m,2H), 1.40-1.31 (m, 2H), 1.09 (d, J=7.7 Hz, 3H), 1.07 (d, J=7.5 Hz, 3H),1.05-0.94 (m, 42H), 0.93-0.90 (m, 2H), 0.86 (d, J=6.6 Hz, 3H), 0.81 (d,J=6.3 Hz, 3H), 0.21-0.13 (m, 24H); ¹³C NMR (75 MHz, CDCl₃) δ 159.7,144.6, 144.4, 134.4, 133.0, 131.9, 131.8, 128.7, 127.7, 127.3, 126.8,126.4, 113.4, 100.8, 86.7, 81.6, 81.3, 73.4, 72.8, 72.0, 66.6, 65.2,55.1, 43.1, 42.3, 39.7, 38.2, 35.4, 35.3, 31.3, 30.8, 30.7, 30.3, 26.2,26.1, 26.04, 25.97, 19.5, 18.8, 18.4, 18.1, 16.6, 14.6, 12.2, 9.1, −2.8,−3.4, −3.6, −3.9, −4.0, −4.1, −4.3; LRMS (ESI) 1327.9 [M+Na]+, 1037.9,803.6, 647.6, 619.6, 413.3, 359.2, 229.1; HRMS (ESI) calcd forC₇₈H₁₂₈O₈Si₄Na 1327.8584 [M+Na]+, found 1327.8622; [α]²⁰ _(D) +5.9 (c0.3, CHCl₃).

(2S,3S,4R,5S,8S,10R,11R,12S,13Z,15S,17S,18S,19E)-3-(4-Methoxybenzyloxy)-5,11,15,17-tetrakis(tert-butyldimethylsilyloxy)-2,4,8,10,12,18-hexamethyl-21-(trityloxy)henicosa-13,19-dien-1-ol(102). The procedure for 93 was used with 101 (0.61 g, 0.47 μmol), DIBAL(4.6 mL, 4.6 mmol) to yield 0.53 g (87%) of the product by flash columnchromatography (EtOAc/Hexane 0.5:9.5) as a colorless oil: IR (CHCl₃)3453, 2956, 2929, 1514, 1471, 1251, 1075, 835, 773 cm⁻¹; ¹H NMR (300MHz, CDCl₃) δ 7.56-7.52 (m, 6H), 7.38-7.26 (m, 11H), 6.96-6.93 (m, 2H),5.91 (dd, J=15.7, 6.0 Hz, 1H), 5.64 (dt, J=15.4, 5.5 Hz, 1H), 5.55-5.50(m, 1H), 5.42 (dd, J=11.1, 8.4 Hz, 1H), 4.70-4.58 (m, 3H), 4.01 (m, 1H),3.83 (s, 3H), 3.79 (m, 2H), 3.67-3.61 (m, 3H), 3.35 (m, 1H), 3.30 (m1H), 2.72 (m, 1H), 2.48 (m, 1H), 1.93 (m, 2H), 1.76-1.55 (m, 3H),1.51-1.26 (m, 1H), 1.10 (d, J=6.6 Hz, 3H), 1.09 (d, J=6.6 Hz, 3H), 1.07(d, J=6.7 Hz, 3H), 1.01-0.98 (m, 39H), 0.93-0.89 (m, 2H), 0.86 (d, J=6.6Hz, 3H), 0.78 (d, J=4.6 Hz, 3H), 0.21-0.13 (m, 24H); ¹³C NMR (75 MHz,CDCl₃) δ 159.2, 144.5, 144.4, 134.3, 133.1, 131.7, 130.6, 129.1, 128.6,127.6, 126.8, 126.7, 126.4, 113.8, 86.7, 85.1, 81.3, 74.9, 74.4, 72.8,66.5, 65.9, 65.1, 55.1, 43.0, 42.3, 41.8, 40.1, 38.4, 35.3, 35.1, 32.8,30.7, 30.5, 26.2, 26.1, 26.0, 25.9, 19.5, 18.6, 18.4, 18.13, 18.10,16.5, 15.4, 14.6, 10.5, −2.8, −3.4, −3.6, −3.9, −4.0, −4.2, −4.4; LRMS(ESI) 1329.8 [M+Na]+, 801.6, 659.3, 637.3, 437.2, 243.1; HRMS (ESI)calcd for C₇₈H₁₃₀O₈Si₄Na 1329.8741 [M+Na]+, found 1329.8788; [α]²⁰ _(D)−9.8 (c 2.6, CHCl₃).

((2E,4S,5S,7S,8Z,10S,11R,12R,14S,17S,18R,19S,20S,21Z)-19-(4-Methoxybenzyloxy)-5,7,11,17-tetrakis(tert-butyldimethylsilyloxy)-4,10,12,14,18,20-hexamethyltetracosa-2,8,21,23-tetraenyloxy)triphenylmethane(103). The procedure for 94 was used with 102 (0.52 g, 0.40 μmol),Dess-Martin reagent (0.25 g, 0.59 mmol) and 1-bromoallyl trimethylsilane(0.49 g, 2.0 mmol), CrCl₂ (0.41 g, 3.32 mmol) and NaH (0.20 g, 8.0 mmol)to yield 0.46 g (88%) of the product by flash column chromatography(EtOAc/hexane 1:19) as a colorless oil: IR (CHCl₃) 2956, 2856, 1614,1514, 1471, 1249, 1074, 835, 773 cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ7.59-7.56 (m, 6H), 7.41-7.27 (m, 11H), 6.98-6.95 (m, 2H), 6.71 (ddd,J=16.7, 10.6, 10.5 Hz, 1H), 6.14 (t, J=11.0 Hz, 1H), 5.94 (dd, J=15.6,5.6 Hz, 1H), 5.80-5.67 (m, 2H), 5.64-5.55 (m, 1H), 5.46 (dd, J=11.0, 8.5Hz, 1H), 5.31 (d, J=16.8 Hz, 1H), 5.21 (d, J=10.2 Hz, 11H), 4.70-4.62(m, 3H), 4.04 (m, 1H), 3.86 (s, 3H), 3.69 (d, J=4.7 Hz, 1H), 3.34 (m,2H), 2.96 (m, 1H), 2.77 (m, 1H), 2.51 (m, 1H), 1.93 (m, 1H), 1.78 (m,1H), 1.75-1.63 (m, 3H), 1.57-1.31 (m, 5H), 1.21 (d, J=6.7 Hz, 3H), 1.15(d, J=6.1 Hz, 3H), 1.12 (d, J=6.7 Hz, 3H), 1.00 (d, J=7.3 Hz, 3H),1.05-1.01 (m, 36H), 0.96-0.93 (m, 2H), 0.89 (d, J=6.7 Hz, 3H), 0.81 (d,J=5.3 Hz, 3H), 0.25-0.11 (m, 24H); ¹³C NMR (75 MHz, CDCl₃) δ 159.1,146.2, 144.6, 144.4, 134.4, 134.3, 132.2, 131.3, 130.2, 129.0, 128.7,127.7, 126.8, 126.5, 117.5, 113.7, 86.7, 84.9, 81.4, 74.9, 73.1, 72.9,66.6, 65.2, 55.1, 43.1, 42.9, 42.3, 40.4, 35.9, 35.6, 35.3, 35.1, 34.5,30.2, 29.4, 26.3, 26.1, 26.0, 19.6, 18.8, 18.6, 18.5, 18.2, 18.14,18.11, 16.5, 14.7, 10.5, −1.1, −2.8, −3.0, −3.3, −3.5, −3.9, −4.2, −4.3;LRMS (ESI) 1351.8 [M+Na]+, 911.1, 837.1, 763.1, 689.1, 541.1, 413.2;HRMS (ESI) calcd for C₈₁H₁₃₂O₇Si₄Na 1351.8948 [M+Na]+, found 1351.8998;[α]²⁰ _(D) −9.3 (c 1.5, CHCl₃).

(2E,4S,5S,7S,8Z,10S,11R,12R,14S,17S,18R,19S,20S,21Z)-19-(4-Methoxybenzyloxy)-5,7,11,17-tetrakis(tert-butyldimethylsilyloxy)-4,10,12,14,18,20-hexamethyltetracosa-2,8,21,23-tetraen-1-ol(104). The procedure for 95 was used with 103 (0.33 g, 0.25 μmol) andZnBr (0.28 g, 1.25 mmol) to yield 0.18 g (65%) of the product by flashcolumn chromatography (EtOAc/hexane 1:9) as a colorless oil: IR (CHCl₃)3417, 2956, 2856, 1613, 1514, 1471, 1250, 1074, 836, 773 cm⁻¹; ¹H NMR(300 MHz, CDCl₃) δ 7.31-7.27 (m, 2H), 6.90-6.87 (m, 2H), 6.60 (ddd,J=16.9, 10.6, 10.5 Hz, 1H), 6.04 (t, J=11.0 Hz, 1H), 5.81 (dd, J=15.7,5.9 Hz, 1H), 5.67-5.60 (m, 2H), 5.51-5.44 (m, 1H), 5.34 (dd, J=11.2, 8.7Hz, 1H), 5.21 (d, J=16.8 Hz, 1H), 5.12 (d, J=10.2 Hz, 1H), 4.60-4.52 (m,3H), 4.10 (d, J=5.7 Hz, 1H), 3.91 (m, 1H), 3.81 (s, 3H), 3.59 (m, 1H),3.31-3.23 (m, 2H), 2.86 (m, 1H), 2.65 (m, 1H), 2.40 (m, 1H), 1.82 (m,1H), 1.66-1.42 (m, 5H), 1.36-1.20 (m, 3H), 1.11 (d, J=6.8 Hz, 3H), 1.03(d, J=7.3 Hz, 3H), 1.01 (d, J=6.6 Hz, 3H), 0.99 (d, J=5.8 Hz, 3H),0.94-0.89 (m, 38H), 0.84 (d, J=7.2 Hz, 3H), 0.82 (d, J=6.4 Hz, 3H),0.13-0.00 (m, 24H); ¹³C NMR (75 MHz, CDCl₃) δ 159.0, 135.0, 134.5,133.2, 132.2, 131.5, 131.4, 129.1, 129.0, 128.7, 117.4, 113.7, 84.8,81.4, 74.8, 73.1, 72.7, 66.5, 64.1, 55.2, 42.8, 42.7, 42.0, 40.4, 35.9,35.4, 35.2, 34.4, 30.3, 29.4, 26.3, 26.03, 26.97, 25.95, 19.6, 18.7,18.6, 18.5, 18.1, 16.6, 14.7, 10.5, −2.8, −3.4, −3.5, −4.0, −4.1, −4.2,−4.3, −4.4; LRMS (ESI) 1109.8 [M+Na]+, 707.2, 633.2, 541.1, 429.1,355.1; HRMS (ESI) calcd for C₆₂H₁₁₈O₇Si₄Na 1109.7852 [M+Na]+, found1109.7874; [α]²⁰ _(D) −15.0 (c 0.94, CHCl₃).

(2Z,4E,6S,7S,9S,10Z,12S,13R,14R,16S,19S,20R,21S,22S,23Z)-Methyl-21-(4-methoxybenzyloxy)-7,9,13,19-tetrakis(tert-butyldimethylsilyloxy)-6,12,14,16,20,22-hexamethylhexacosa-2,4,10,23,25-pentaenoate(105). The procedure for 96 was used with 104 (0.18 g, 0.16 μmol),Dess-Martin reagent (0.10 g, 0.24 mmol) andbis(2,2,2-trifluoroethyl)-(methoxycarbonylmethyl)phosphate (0.041 mL,0.19 μmol), 18-crown-6 (0.21 g, 0.19 mmol) and KHMDS (0.39 mL, 0.19mmol) to yield 0.16 g (84%) of the product by flash columnchromatography (EtOAc/hexane 1:19) as a colorless oil: IR (CHCl₃) 2956,2929, 2856, 1721, 1514, 1462, 1250, 1174, 1074, 836, 773 cm⁻¹; ¹H NMR(300 MHz, CDCl₃) δ 7.38 (dd, J=15.4, 11.2 Hz, 1H), 7.32-7.29 (m, 2H),6.91-6.86 (m, 2H), 6.60 (ddd, J=17.0, 10.6, 10.5 Hz, 1H), 6.56 (t,J=11.3 Hz, 1H), 6.23 (dd, J=15.5, 5.9 Hz, 1H), 6.05 (t, J=11.0 Hz, 1H),5.68-5.56 (m, 2H), 5.50-5.43 (m, 1H), 5.38-5.31 (m, 1H), 5.23 (d, J=16.8Hz, 1H), 5.12 (d, J=10.2 Hz, 1H), 4.61-4.52 (m, 3H), 3.98 (m, 1H), 3.81(s, 3H), 3.73 (s, 3H), 3.59 (m, 1H), 3.29-3.23 (m, 2H), 2.86 (m, 1H),2.68-2.59 (m, 2H), 1.83 (m, 1H), 1.63-1.51 (m, 2H), 1.49-1.35 (m, 3H),1.34-1.22 (m, 2H), 1.12 (d, J=6.8 Hz, 3H), 1.07 (d, J=6.9 Hz, 3H), 1.03(d, J=5.0 Hz, 3H), 1.01 (d, J=6.7 Hz, 3H), 0.94-0.89 (m, 38H), 0.84 (d,J=6.6 Hz, 3H), 0.80 (d, J=6.1 Hz, 3H), 0.14-0.00 (m, 24H); ¹³C NMR (75MHz, CDCl₃) δ 166.8, 159.1, 147.2, 145.7, 134.4, 133.2, 132.2, 131.6,131.4, 129.2, 129.0, 126.4, 117.5, 115.2, 113.7, 84.7, 81.5, 74.9, 73.0,72.7, 66.4, 55.2, 50.9, 42.9, 42.8, 42.6, 40.3, 35.9, 35.4, 35.2, 34.4,30.4, 29.5, 26.3, 26.03, 25.98, 19.6, 18.8, 18.7, 18.5, 18.1, 16.7,14.5, 10.5, −2.8, −3.3, −3.5, −4.0, −4.1, −4.17, −4.22, −4.4; LRMS (ESI)1163.8 [M+Na]+, 1009.7, 877.6, 513.4; HRMS (ESI) calcd forC₆₅H₁₂₀O₈Si₄Na 1163.7958 [M+Na]+, found 1163.7981; [α]²⁰ _(D) −45.3 (c0.36, CHCl₃).

(2Z,4E,6S,7S,9S,10Z,12S,13R,14R,16S,19S,20R,21S,22S,23Z)-Methyl-7,9,13,19-tetrakis(tert-butyldimethylsilyloxy)-21-hydroxy-6,12,14,16,20,22-hexamethylhexacosa-2,4,10,23,25-pentaenoate(106). The procedure for 97 was used with 105 (0.16 g, 0.14 μmol) andDDQ (0.034 g, 0.15 mmol) to yield 0.13 g (90%) of the product by flashcolumn chromatography (EtOAc/hexane 1:19) as a colorless oil: IR (CHCl₃)3512, 2956, 2929, 2857, 1772, 1639, 1471, 1462, 1255, 1193, 1076, 836,773 cm⁻¹; ¹H NMR (300 MHz, CDCl₃) δ 7.35 (dd, J=15.4, 11.2 Hz, 1H), 6.61(ddd, J=16.9, 10.6, 10.5 Hz, 1H), 6.53 (t, J=11.3 Hz, 1H), 6.19 (dd,J=15.6, 6.0 Hz, 1H), 6.09 (t, J=11.0 Hz, 1H), 5.56 (d, J=11.3 Hz, 1H),5.44 (t, J=11.0 Hz, 1H), 5.31 (dd, J=11.0, 8.4 Hz, 1H), 5.19 (d, J=16.8Hz, 1H), 5.10 (d, J=10.1 Hz, 1H), 4.55 (m, 1H), 3.94 (m, 1H), 3.71 (s,3H), 3.25 (m, 2H), 2.75 (m, 1H), 2.58 (m, 2H), 1.72 (m, 1H), 1.67-1.60(m, 1H), 1.59-1.49 (m, 2H), 1.40 (m, 1H), 1.32-1.25 (m, 2H), 1.22-1.13(m, 2H), 1.04 (d, J=7.0 Hz, 3H), 1.01 (d, J=7.1 Hz, 3H), 0.99 (d, J=6.8Hz, 3H), 0.91-0.86 (m, 41H), 0.81 (d, J=6.5 Hz, 3H), 0.79 (d, J=6.0 Hz,3H), 0.11-0.05 (m, 24H); ¹³C NMR (75 MHz, CDCl₃) δ 166.8, 147.2, 145.6,136.4, 133.2, 132.6, 131.5, 129.5, 126.4, 117.3, 115.2, 81.3, 78.6,74.3, 72.7, 66.4, 50.9, 42.9, 42.6, 39.7, 36.2, 35.8, 35.4, 35.3, 34.1,32.4, 30.6, 26.3, 26.0, 25.9, 19.6, 19.2, 18.5, 18.1, 18.0, 17.4, 16.7,14.5, 10.9, −2.8, −3.4, −3.5, −4.06, −4.11, −4.2, −4.3, −4.4; LRMS (ESI)1043.7 [M+Na]+; HRMS (ESI) calcd for C₅₇H₁₁₂O₇Si₄Na 1043.7383 [M+Na]+,found 1043.7424; [α]²⁰ _(D) −37.8 (c 1.4, CHCl₃).

(2Z,4E,6S,7S,9S,10Z,12S,13R,14R,16S,19S,20R,21S,22S,23Z)-7,9,13,19-tetrakis(tert-Butyldimethylsilyloxy)-21-hydroxy-6,12,14,16,20,22-hexamethylhexacosa-2,4,10,23,25-pentaenoicacid (107). The procedure for 99 was used with 106 (0.13 g, 0.13 μmol)and 1N KOH (1.2 mL, 1.3 mmol), 2,4,6-trichlorobenzoyl chloride (0.094mL, 0.60 μmol) and Et₃N (0.10 mL, 0.78 mmol), 4-DMAP (60 mL, 1.3 mmol)to yield 0.054 g (45% for 2 steps) of the product by flash columnchromatography (EtOAc/hexane 1:19) as a colorless oil: (seco acid) IR(CHCl₃) 2956, 2857, 1692, 1634, 1471, 1462, 1254, 1076, 836, 773 cm⁻¹;¹H NMR (300 MHz, CDCl₃) δ 7.34 (dd, J=15.2, 11.3 Hz, 1H), 6.66 (ddd,J=16.8, 10.8, 10.6 Hz, 1H), 6.62 (t, J=11.3 Hz, 1H), 6.23 (dd, J=15.3,6.0 Hz, 1H), 6.09 (t, J=11.0 Hz, 1H), 5.57 (d, J=11.2 Hz, 1H), 5.48-5.42(m, 1H), 5.35-5.28 (m, 1H), 5.20 (d, J=16.8 Hz, 1H), 5.10 (d, J=10.2 Hz,1H), 4.55 (m, 1H), 3.95 (m, 1H), 3.74 (m, 1H), 3.26 (m, 1H), 2.78 (m,1H), 2.58 (m, 2H), 1.75-1.64 (m, 2H), 1.62-1.49 (m, 3H), 1.44-1.37 (m,1H), 1.32-1.19 (m, 3H), 1.04 (d, J=7.0 Hz, 3H), 1.01 (d, J=7.0 Hz, 3H),1.00 (d, J=6.4 Hz, 3H), 0.95-0.86 (m, 41H), 0.82 (d, J=7.1 Hz, 3H), 0.81(d, J=6.4 Hz, 3H), 0.12-0.05 (m, 24H); ¹³C NMR (75 MHz, CDCl₃) δ 171.5,148.3, 147.4, 136.4, 133.1, 132.6, 131.5, 129.5, 126.6, 117.3, 115.0,81.3, 78.6, 74.3, 72.7, 66.4, 43.0, 42.7, 39.7, 36.2, 35.8, 35.5, 35.3,34.1, 32.4, 30.6, 26.3, 26.0, 25.94, 25.92, 19.6, 19.2, 18.5, 18.1,18.0, 17.4, 16.7, 14.5, 11.0, −2.8, −3.4, −3.5, −4.1, −4.25, −4.32,−4.7; LRMS (ESI) 1029.7 [M+Na]+, 915.8; HRMS (ESI) calcd forC₅₆H₁₁₀O₇Si₄Na 1029.7226 [M+Na]+, found 1029.7252; [α]²⁰ _(D) −32.7 (c0.51, CHCl₃).

8(S),10(S),14(R),20(S)-Tetrahydroxy-7(S),13(S),15(R),17(S),21(S)-pentamethyl-22(S)-(1(S)-methyl-penta-2,4-dienyl)oxacyclodocosa-3(Z),5(E),11(Z)-trien-2-one(194, YSS675-1) and8(S),10(S),14(R),20(S)-Tetrahydroxy-7(S),13(S),15(R),17(S),21(S)-pentamethyl-22(S)-(1(S)-methyl-penta-2,4-dienyl)oxacyclodocosa-3(E),5(E),11(Z)-trien-2-one(108, YSS675-2). The procedure for 100 was used with 107 (0.054 g, 0.054μmol) in 3N HCl (5 mL) and THF (2 mL) to yield 13 mg (45%) of 108 and4.5 mg (15%) of the 109 by flash column chromatography (EtOAc/hexane7:3) as a colorless oil: (108) IR (CHCl₃) 3416, 2961, 2927, 2873, 1692,1635, 1455, 1421, 1379, 1190, 1086, 998 cm⁻¹; ¹H NMR (600 MHz, CD₃OD) δ7.26 (dd, J=15.2, 11.3 Hz, 1H), 6.65 (ddd, J=16.8, 10.6, 10.3 Hz, 1H),6.56 (t, J=11.3 Hz, 1H), 5.97 (t, J=10.9 Hz, 1H), 5.91 (dd, J=15.2, 9.3Hz, 1H), 5.49 (d, J=10.7 Hz, 1H), 5.42 (t, J=8.6 Hz, 1H), 5.20 (t,J=10.4 Hz, 1H), 5.15 (dd, J=16.9, 1.3 Hz, 1H), 5.08 (d, J=10.1 Hz, 1H),5.05 (dd, J=9.6, 1.3 Hz, 1H), 4.62 (ddd, J=11.5, 7.7, 4.3 Hz, 1H), 3.65(ddd, J=10.0, 7.3, 3.1 Hz, 1H), 3.07 (dd, J=6.7, 4.0 Hz, 1H), 3.01 (m,1H), 2.66 (m, 1H), 2.26 (m, 1H), 1.90 (m, 1H), 1.66 (ddd, J=11.5, 8.4,3.4 Hz, 1H), 1.49 (ddd, J=14.1, 10.0, 4.0 Hz, 1H), 1.45 (m, 1H), 1.38(m, 1H), 1.32 (m, 1H), 1.27 (m, 1H), 1.11 (d, J=6.7 Hz, 3H), 1.06 (m,1H), 1.03 (ddd, J=11.3, 7.2, 4.4 Hz, 3H), 1.01 (d, J=6.9 Hz, 3H), 0.99(d, J=6.7 Hz, 3H), 0.96 (d, J=7.0 Hz, 3H), 0.93 (m, 1H), 0.89 (m, 1H),0.85 (d, J=6.7 Hz, 3H), 0.75 (d, J=5.9 Hz, 3H); ¹³C NMR (150 MHz, CD₃OD)δ 168.1, 148.7, 146.6, 135.7, 134.0, 133.7, 132.9, 131.1, 128.2, 118.0,117.0, 80.9, 78.4, 74.4, 72.4, 66.3, 46.4, 43.4, 42.5, 40.9, 36.3,35.90, 35.88, 35.7, 31.8, 31.5, 19.9, 19.3, 18.3, 17.5, 8.5; LRMS (ESI)555.3 [M+Na]+, 537.4; HRMS (ESI) calcd for C₃₂H₅₂O₆ 555.3662 [M+Na]+,found 555.3680; [α]²⁰ _(D) +76.5 (c 0.52, MeOH): (109) IR (CHCl₃) 3428,2962, 2928, 1690, 1635, 1380, 1243, 1145, 1064, 1000 cm⁻¹; ¹H NMR (600MHz, CD₃OD) δ 7.20 (dd, J=15.2, 10.8 Hz, 1H), 6.65 (ddd, J=17.0, 10.6,10.5 Hz, 1H), 6.38 (dd, J=15.5, 5.4 Hz, 1H), 6.23 (dd, J=14.4, 10.9 Hz,1H), 5.95 (t, J=1.0 Hz, 1H), 5.77 (d, J=15.3 Hz, 1H), 5.40-5.39 (m, 2H),5.23 (t, J=10.5 Hz, 1H), 5.13 (d, J=18.1 Hz, 1H), 5.12 (dd, J=8.2, 1.5Hz, 1H), 5.07 (d, J=10.2 Hz, 1H), 4.66 (m, 1H), 3.90 (ddd, J=7.6, 5.1,2.5 Hz, 1H), 3.22 (dd, J=9.8, 7.9 Hz, 1H), 3.04 (m, 1H), 2.95 (dd,J=9.7, 2.1 Hz, 1H), 2.72 (m, 1H), 2.65 (m, 1H), 1.83 (m, 1H), 1.58 (m,1H), 1.46 (m, 1H), 1.35-1.23 (m, 4H), 1.05 (d, J=6.8 Hz, 3H), 1.04 (d,J=6.9 Hz, 3H), 0.98 (d, J=6.8 Hz, 3H), 0.97 (d, J=7.0 Hz, 3H), 0.94 (m,2H), 0.78 (m, 1H), 0.71 (d, J=6.4 Hz, 3H), 0.68 (d, J=6.5 Hz, 3H); ¹³CNMR (150 MHz, CD₃OD) δ 169.4, 147.5, 147.4, 135.9, 134.3, 133.7, 131.0,128.9, 120.0, 118.0, 80.5, 78.5, 72.6, 72.0, 65.2, 43.6, 42.6, 42.1,39.3, 36.3, 35.8, 35.6, 35.3, 31.4, 29.7, 19.3, 18.5, 17.4, 17.1, 14.8,9.0; LRMS (ESI) 555.5 [M+Na]+; HRMS (ESI) calcd for C₃₂H₅₂O₆ 555.3662[M+Na]+, found 555.3687; [α]²⁰ _(D) −17.3 (c 0.15, MeOH).

Biology

Tubulin polymerization assay. Tubulin assembly was monitoredturbidimetrically in Gilford 250 spectrophotometers equipped withelectronic temperature controllers as described previously (ter Haar etal., 1996). The reaction mixtures without the compounds consisted oftubulin (1 mg/ml), heat-treated MAPs (0.75 mg/ml, if present), GTP (100μM, if present), and 0.1M (4-morpholinyl)ethane sulfonate (MeS).Baselines were established after addition of all reaction componentsexcept the compounds to the cuvettes held at 0° C. Compounds, at 10 μMor 40 μM final concentration, were then added and each reaction mixture(0.25 mL final volume) was subjected to the indicated temperaturechanges.

Antiproliferative Assay. The effects of dictyostati and its analogs ongrowth inhibition of parental (A549) and paclitaxel-resistant (1A9/Ptx10and Ptx22) ovarian adenocarcinoma cell lines were evaluated followingthe antiproliferative assay protocol as described earlier (Minguez etal., 2003; Choy et al., 2003; Lazo et al., 2001). Cells were maintainedin RPMI medium with 10% FBS in it, plated in tissue culture plates, andallowed to grow for 48-72 h before transferring them into 96-wellplates. Cells were allowed to attach and grow for 48 h in 96-well platesafter which they were treated with either control (DMSO) or drug intriplicate/quadruplicate. Cells were incubated with the compounds for 72h. Cells were treated with MTS reagent before reading the plate in aDynamax plate reader for determining the cell number. The fifty percentgrowth inhibition values (GI₅₀ values) were calculated for the compoundsagainst all the three cell lines.

Pelleting Assay (determination of EC₅₀). The assay was performed underthree different reaction conditions following the procedure reportedearlier (Gapud et al., 2004). Reaction condition 1 included 0.2 Mmonosodium glutamate (MSG), 10 μM tubulin, 5% DMSO and varyingconcentrations of test agents. Reaction condition 2 included 0.8 M MSG,400 μM GTP, 10 μM tubulin, 5% DMSO, and varying concentrations of testagents. Reaction condition 3 had 0.6 M MSG, 200 μM GTP, and 10 μMtubulin, and 5% DMSO, and varying concentrations of the test agents. Theexperimental protocol for all the three reaction conditions was thefollowing. The reaction mixtures were incubated at room temperature(20-22° C.) for 15 min and spun for 10 min at 14,000 rpm in an Eppendorfmicrotube centrifuge. Aliquots of the supernatants were removed andassayed for protein content by the method of Lowry. The EC₅₀ was definedas drug concentration required to polymerize 50% of tubulin compared tothe pellet found in the DMSO control reaction determined for each testsystem. On average 5.5±4.0% of the tubulin pelleted in the DMSO control.

Multiparameter fluorescence microscopy high information contentcell-based fluorescence screening: HeLa cells growing at log phase weretrypsinized and plated in 40 μL at a density of 7,000-8,000 cells perwell in calf skin collagen I-coated 384-well plates (Falcon #3962;Fisher Scientific). Cells were exposed to test agents or 0.5% DMSOwithin 2-8 h of plating. Concentrated DMSO stock solutions of all testagents were diluted into solutions of HBSS medium plus 10% FBS and addedto the microplate wells (10 μL per well), using an automated liquidhandling system (Biomek® 2000; Beckman-Coulter, Inc.) to provide aserial 2-fold dilution of each test agent. The cells were incubated inthe presence of test agents for 24 h. At the end of the incubation, themedium was removed and replaced with HBSS containing 4% formaldehyde and10 μg/mL Hoechst 33342 (25 μL/well) to fix the cells and fluorescentlylabel their chromatin. After incubation at room temperature for 20-30min, the solution was removed from each well and replaced with HBSS (100μL/well). Further reagent additions were made to the microplates usingthe Biomek 2000. After removing the HBSS from each well, cells werepermeabilized for 5 min at room temperature with 0.5% (w/w) Triton X-100in HBSS (10 μL/well). This step extracts a fraction of the solublecellular components, including soluble tubulin. The wells were washedwith HBSS (100 μL/well), followed by addition of a primary antibodysolution containing mouse anti-α-tubulin (1:3000) and rabbitanti-phosphohistone H3 (1:500) in HBSS (10 μL/well). After 1 h at roomtemperature, the wells were washed with HBSS as above, followed by theaddition of a secondary antibody solution containingfluorescein-5-isothiocyanate (FITC)-labeled donkey anti-mouse (1:300)and Cy3-labeled donkey anti-rabbit (1:300) antibodies diluted in HBSS(10 μL/well). After 1 h at room temperature, the wells were washed asabove, and HBSS was added (100 μL/well). The plates were placed in anArrayScan® HCS Reader with the Target Activation BioApplication Softwarecoupled to Cellomics® Store and the Vhcs™ Discovery Toolbox (Cellomics,Inc.) to analyze images. Briefly, the instrument was used to scanmultiple optical fields, each with multiparameter fluorescence, within asubset of the wells of the 384-well microplate. The BioApplicationsoftware produced multiple numerical feature values, such as subcellularobject intensities, shapes, and location for each cell within an opticalfield. Data were acquired from a minimum of 1,000 cells per well, exceptin cases where added test agents reduced the attachment of cells to thesubstrate. A nuclear mask was generated from Hoechst 33342-stainednuclei, and object identification thresholds and shape parameters wereset such that the algorithm identified over 90% of the nuclei in eachfield. Objects that touched each other or the edge of the image wereexcluded from the analysis. Tubulin mass was defined as the averagegreen (FITC) pixel intensity in an area defined by the Hoechst-definednuclear mask. This cytoplasmic area around the nucleus containscytoskeletal components is a region from which sensitive measurements ofcytoplasmic characteristics can be made. The percentage ofphospho-histone H3 positive cells was defined as the number of cellswhose average red (Cy3) staining intensity exceeded the average Cy3intensity plus two standard deviations of vehicle-treated cells, dividedby the total number of cells.

Radiolabeled ligand binding assays: [³H]Paclitaxel, [³H]discodermolideand [¹⁴C]epothilone B solutions were prepared as 125 μM stock solutionsin 50% DMSO. Radiolabeled compound (final concentration, 4.0 μM) andtest agents at final concentrations noted in the text and tables weremixed in 50 μL of 4:1 (v/v) 0.75 M aqueous MSG/DMSO and warmed to 37° C.Meanwhile, a reaction mixture containing 0.75 M MSG, 2.5 μM tubulin, and25 μM ddGTP was prepared and incubated at 37° C. for 30 min to formmicrotubuless. A 200 μL aliquot of the microtubule mixture was added tothe drug mixtures, and incubation continued for 30 min at 37° C.Reaction mixtures were centrifuged in an Eppendorf 5417C centrifuge at14,000 rpm for 20 min at room temperature. Radiolabel in thesupernatants (100 μL) was determined by scintillation spectrometry.Bound radiolabeled compound was calculated from the total radiolabeladded to each reaction mixture minus the amount of radiolabel found inthe supernatant.

The foregoing description and accompanying drawings set forth thepreferred embodiments of the invention at the present time. Variousmodifications, additions and alternative designs will, of course, becomeapparent to those skilled in the art in light of the foregoing teachingswithout departing from the scope of the invention. The scope of theinvention is indicated by the following claims rather than by theforegoing description. All changes and variations that fall within themeaning and range of equivalency of the claims are to be embraced withintheir scope.

1. A compound having the following formula, or its enantiomer

R² is H, a protecting group, an alkyl group, a benzyl group, a tritylgroup, —SiR^(a)R^(b)R^(c), CH₂OR^(d), or COR^(e); R^(a), R^(b) and R^(c)are independently an alkyl group or an aryl group; R^(d) is an alkylgroup, an aryl group, an alkoxylalkyl group, —RSiR^(a)R^(b)R^(c) or abenzyl group, wherein R^(i) is an alkylene group; R^(e) is an alkylgroup, an allyl group, a benzyl group, an aryl group, an alkoxy group,or —NR^(g)R^(h), wherein R^(g) and R^(h) are independently H, an alkylgroup or an aryl group; R³ is (CH₂), where n is and integer in the rangeof 0 to 5, —CH₂CH(CH₃)—, —CH═CH—, —CH═C(CH₃)—, or —C≡C—; R^(11a) andR^(11b) are independently H, a protecting group, an alkyl group, abenzyl group, a trityl group, —SiR^(a)R^(b)R^(c), CH₂OR^(d), COR^(e), orR^(11a) and R^(11b) together form a portion of six-membered acetal ringcontaining CR^(t)R^(u); R^(t) and R^(u) are independently H, an alkylgroup, an aryl group or an alkoxyaryl group; R¹² is a halogen atom,CH₂OR^(2c), CHO, CO₂R¹⁰, CH═CHCH₂OR^(2c), CH═CHCHO or CH═CHCO₂R¹⁰,wherein R^(2c) is H, a protecting group, an alkyl group, an aryl group,a benzyl group, a trityl group, —SiR^(a)R^(b)R^(c), CH₂OR^(d), orCOR^(e), and R¹⁰ is H or alkyl; and R^(14a) and R^(14b) areindependently H, an alkyl group, a benzyl group, a trityl group,—SiR^(a)R^(b)R^(c), CH₂OR^(d), COR^(e), or R^(14a) and R^(14b) togetherform a six-membered ring containing CR^(v)R^(w), wherein R^(v) and R^(w)are independently H, an alkyl group, an aryl group or an alkoxyarylgroup.
 2. The compound of claim 1 with the following stereostructure, orits enantiomer

wherein R³ is CH₂CH(CH₃)CH₂CH₂, CH═CH, or CH═C(CH₃); and R^(11a) andR^(11b) are H or together form a portion of a six-membered acetal ringcontaining C(H)(p-C₆H₄₀CH₃) or C(CH₃)₂.
 3. A compound having thefollowing formula, or its enantiomer

wherein X is H, NCH₃(OCH₃), or a leaving group; R¹¹ is H, a protectinggroup, an alkyl group, and aryl group, a benzyl group, a trityl group,—SiR^(a)R^(b)R^(c), CH₂OR^(d), or CORE, R^(t) and R^(u) areindependently H, an alkyl group or an aryl group; R¹² is a halogen atom,CH₂OR^(2c), CHO, CO₂R¹⁰, CH═CHCH₂OR^(2c), CH═CHCHO or CH═CHCO₂R¹⁰,wherein R^(2c) is H, a protecting group, an alkyl group, an aryl group,a benzyl group, a trityl group, —SiR^(a)R^(b)R^(c), CH₂OR^(d), orCOR^(e), and R¹⁰ is H or alkyl.
 4. A process for reacting a firstcompound of the following formula, or its enantiomer

wherein R² a protecting group, an alkyl group, an aryl group, a benzylgroup, a trityl group, —SiR^(a)R^(b)R^(c), CH₂OR^(d), or COR^(e); R^(a),R^(b) and R^(c) are independently an alkyl group or an aryl group; R^(d)is an alkyl group, an aryl group, an alkoxylalkyl group,—R^(i)SiR^(a)R^(b)R^(c) or a benzyl group, wherein R^(i) is an alkylenegroup; R^(e) is an alkyl group, an allyl group, a benzyl group, an arylgroup, an alkoxy group, or —NRGR^(h) wherein R^(g) and R^(h) areindependently H, an alkyl group or an aryl group; R¹⁶ is H or alkyl; andR¹⁷ is CH₂OR^(2f), CHO, CO₂R^(v), wherein R^(2f) is H, an alkyl group,an aryl group, a benzyl group, a trityl group, —SiR^(a)R^(b)R^(c),CH₂OR^(d), or COR^(e); R²⁵CH═CX₂, C≡CH or C═CSiR^(a)R^(b)R; X is Cl, Bror I with a second compound of the following formula, or its enantiomer

wherein X is NCH₃(OCH₃), or a leaving group; R¹¹ an alkyl group, andaryl group, a benzyl group, a trityl group, —SiR^(a)R^(b)R^(c),CH₂OR^(d), COR^(e); R¹² is a halogen atom, CH₂OR^(2c), CO₂R^(v),CH═CHCH₂OR^(2c) or CH═CHCO₂R^(v), wherein R^(2c) is an alkyl group, anaryl group, a benzyl group, a trityl group, —SiR^(a)R^(b)R^(c),CH₂OR^(d), or COR^(e), and R^(v) is alkyl, comprising metalation of thefirst compound and addition of the second compound to produce a compoundof the following formula, or its enantiomer

wherein R²⁴ is C≡C.